As they know from their own relatively recent coming of age, they'll never see their daughters as debutantes or throw formal 21st birthday parties for their sons: it is only in early childhood that today's offspring are biddable.The danger here is that children become mere spectators, even extras, at what is supposed to be their own event.I suggested to Susie Burrows that party bags must come to an end at nine or 10, when, instead of a tea party for the whole class, the child will take a smaller group of friends off for a treat."Oh, no," she said, "it's still expected. All this in addition to an entertainer, a custom-baked cake, possibly professional caterers, and (even expensive houses in Battersea being small) the hire of a local hall.So, by some mysterious transference, the children's birthday party has turned into a battleground of social ambitions, ripe for the attention of a contemporary Jane Austen. No one considers the embarrassment of the mother who can't afford to keep up, or the danger of turning our children into spoilt little brats.Or is it merely a harmless indulgence in parental pride? After all, today's Mrs Bennets aren't trying to marry off their five-year-olds, they just want the fun of dressing them up and clucking over them. "People just feel that they have to provide them, so I try to stock as many comparatively cheap things as I can," she says, waving towards shelves of plastic goodies costing as little as 12p a throw. Mothers spend an awful lot of time and money organising them." The competition leads to escalating levels of expenditure on themed party accessories, with matching invitations, disposable plates and cups, balloons and party bags, in pirate or dinosaur designs for boys, princesses (yes, still) and fairies for girls.

"Far worse than giving a dinner party, and almost as expensive. They want something more expensive."The something more expensive is preferably made of wood, such as a mini football rattle costing pounds 2.45, or has long-term usefulness, such as a skipping rope or a pack of cards.It's My Party will either fill bags to a particular budget - and orders of 30 bags at pounds 4.50 each are not unknown - or bag and label goodies of the parents' choice.But even with the help of a specialist shop, budgeting and choice is no easy matter "It's very tricky," says Susie. But it's amazing how many people - and I'm talking about the parents, the mothers - don't want them. "After all, that's what children want - lots of little things. This means that when you pay 20p for a bracelet, you get a couple of pence-worth of parts and labour, and about 10p-worth of round-the-world shipping costs.Given that a large slice of Susie's income derives from providing party bags, she is surprisingly sympathetic to the plight of the reluctant parent. Naturally, we were pleased with this unexpected show of generosity, but I remember also feeling distinctly suspicious at what seemed an overdone gesture on a par with offering a third or fourth helping of ice cream.So how, in the space of 30 years, has a rare and lavish gesture turned into a kitsch ritual of conspicuous consumption? I asked Susie Burrows, the proprietor of It's My Party, a small specialist shop in Battersea, south London, who confirmed my suspicion that it is a relatively recent import from America, like trick-or-treating on Hallowe'en, which has taken root on these shores in the past 15 years.If proof were needed, most of Susie's stock of small games and toys is manufactured in the Far East but distributed from the United States (where, incidentally, they are known as "party favors"). The requirement was so obvious that they didn't see the need to discuss it with us.Back in the early Sixties, when I was on the birthday party circuit myself, only the lucky few went home with presents.

Prizes had to be won, either by luck (pass the parcel) or by physical prowess (musical chairs, statues). There were, on occasion, tears of disappointment, and perhaps it was unfair that budding Daley Thompsons won more than their share, but we learned that the fun came from taking part (and that prizes were all the sweeter for their rarity).Only once was I presented with a party bag (although it was called a going home present). The leisure centre, being in the business of keeping its customers happy, provided party bags as part of the deal. I argued that we were already hiring a mini-gym and laying on tea at the leisure centre; what more could the kids (or their parents) want?As it turned out, my gesture was in vain. A telephone survey of friends around the country revealed that the practice is all but universal in Nineties Britain.

Most parents shrug and offer the rationale that, well, everyone else does it, so the children now expect something to go home with.When, earlier this year, I decided finally to put my foot down and to ban party bags from my younger son's fifth birthday, there was a certain amount of agonising in the household over whether or not I would go down in local lore as the Scrooge of the reception class. "Where's my party bag?" pipes up a five-year-old, and I swap an embarrassed glance with the mother. This little exchange, with minor variations, has been repeated with depressing regularity at children's parties I have thrown or attended as a chauffeur in eight years of fatherhood. My response has varied from a clipped "You'll get it at the end", said through clenched teeth, to a defiant "There aren't any". Why do we go along with this ritual of handing out little bags of plastic tack and yet more tooth-rotting sweets to the crisped-out, sugar-satiated punters at the end of the party? We all know that most of the contents will be consumed, spilled or broken by overtired, over-excited children on the short journey home.But go along with it we do. Crisps and jellies are ready, the games are all set and the furniture pushed to one side when the first wave of guests arrives.