Britain may be basking in Olympic glory, but at the 'People's Games' many of the host nation's team come from privileged families and compete in costly sports.

A disproportionate number of British competitors at London 2012 were educated at fee-paying schools, and the government faces growing calls to tackle the perceived elitism of top-level sport.

Queen Elizabeth II's granddaughter Zara Phillips - who won a silver medal in the three-day eventing - was following a tradition of British royals competing at the Olympics, but one of her schoolmates took home a medal too.

Heather Stanning, who with Helen Glover won Britain's first gold medal of the Games in the women's double sculls, attended the elite Gordonstoun boarding school in Scotland, where Phillips also studied.

Some 20 percent of Britain's team were privately educated, and in rowing, sailing and the equestrian events -- all British specialities, and all seen as expensive pastimes -- the figure rises to a third.

In contrast, just seven percent of the overall British population attend fee-paying schools, with the other 93 percent studying at state-funded institutions.

British Olympic Association chief Lord Colin Moynihan last week condemned the dominance of private-school-educated athletes in the British Olympic team as "one of the worst statistics in British sport".

"There is so much talent out there in the 93 percent that should be identified and developed," said Moynihan, who is himself an aristocrat.

Calling for a dramatic overhaul of school sports policy, Moynihan said it was "wrong and unacceptable" that so many top British athletes came from private schools.

Alan Bairner, Professor of Sport and Social Theory at Loughborough University, said a combination of factors was responsible.

"One is that they have incredible sports facilities at the private schools, and specialist coaches," he said.

"In contrast, there's no doubt that in state schools today there are fewer opportunities to play sports of all sorts than there were thirty or forty years ago."

"State school teachers felt that they were being exploited by taking teams to matches on Saturdays and so on, and they cut down on the commitment they were willing to make -- which of course hasn't happened in the private schools."

Several of Britain's most exclusive boarding schools are famous for their ability to produce Olympians.

With 130 coaches, an Olympic-sized pool and pitches that are regularly used by international teams, Millfield School in south-west England has produced five members of the British squad.

Three others -- including rower Lawrence Clarke, the heir apparent to a baronetcy -- attended Eton College, the former school of Prime Minister David Cameron which is hosting the Olympic rowing at its Eton Dorney lake.

In the allegedly 'posh' disciplines of rowing, sailing and equestrianism, Bairner said the dominance of private schools came partly down to money and facilities, and partly down to working-class perceptions of the sports.

"A lot of people at private schools may have had the opportunity to sail or to row -- whereas if you live in inner-city Birmingham, I imagine you're a long way from your nearest sailing club," he said.

"But it's also that, while in theory a sport may be perfectly accessible, in reality people exclude themselves and say: 'This is not for us.'"

Simon Dickie, youth manager at British Rowing, said the sport suffered from a long association with boarding schools and the elite universities of Oxford and Cambridge -- but laboured to recruit talent from different backgrounds.

"Rowing does have a posh image that I don't think we'll ever totally eradicate," he admitted. "But we can work hard to have a more balanced approach."

The sport runs talent-scouting operations in schools and universities, and has placed rowing machines at 2,000 schools to encourage interest from an early age.

"At the Atlanta and Sydney Olympics the vast majority of our athletes started rowing at an independent school, but at London 2012 more than half of the British rowing team came from the state school sector," Dickie said.

Some of the biggest British stars of these Games hail from modest families -- heptathlete Jessica Ennis' parents are a decorator and social worker, while runner Mo Farah was born in Somalia before his family came to Britain. He attended a state school in London.

But Bairner said the British track and field squad was particularly diverse because of the relatively low cost of discovering a talent for athletics.

"The basics of running, throwing and jumping, are things that one can do cheaply compared to having a boat to sail in," he said.

One result of the lingering class divide in sport, he warned, is that there is likely to be a pool of untapped talent in Britain.

"For a sport like tennis, for example, which is pretty elitist and very white, there must be potentially much better players out there," he said.