Qatar has again been accused of employing migrant workers as sports fans in an effort to make largely empty arenas appear full.

Around 150 workers were paid to be fans at the Qatar Open of international beach volleyball last month – an event that the FIVB, volleyball’s governing body, said on its website had “brought out the crowds”.

But migrants from Ghana, Kenya, Nepal and elsewhere, who work in Qatar as bus and taxi drivers for the state-owned transport company and for other employers, said they were there for the money, not the volleyball.

The French players Edouard Rowlandson and Youssef Krou were winning their bronze-medal match as the workers arrived to fill seats, making the arena appear almost full. Rowlandson called the scene “bizarre … but we prefer that to playing in front of nobody”.

The FIVB’s media director, Richard Baker, said the federation was unaware of the fake fans, and would seek clarification from Qatari organisers.

Underway at the #DohaOpen and centre court filling up nicely for the qualifiers - nine matches in total for today pic.twitter.com/TNvil8A2u5 — Beach Volleyball (@FIVBWorldTour) November 4, 2014

The issue is not a new one. A survey of 1,079 Qatar residents published in January by the Ministry of Development Planning and Statistics suggested that paid fans may be turning Qataris off sport.

The ministry said two-thirds of Qataris surveyed did not attend any football matches during the previous season and two-thirds of respondents cited “the spread of paid fans” as a significant factor in keeping audiences away.

At the volleyball, some for-hire spectators were offered less than others. Security guards and office boys from Kenya said a promise of 20 riyals (£3.50) each drew 40 people on to their bus. A Nigerian said he, too, was getting just 20.

Numerous workers said they regularly make up numbers at sports events. Qatar league football games pay 20 or 25 riyals, they said. A Kenyan said he made 50 riyals at handball.

At the volleyball arena, which had free Wi-Fi, workers were seen checking messages and emails on their phones, ignoring a crowd organiser waving a plastic hand who urged them to clap to Daft Punk’s Get Lucky.

Pitching successfully in November to track and field’s governing body to host its world athletics championships in 2019, the Qatar bid presenter, Aphrodite Moschoudi, said: “Qatar has a true passion for sports. Everything in our country revolves around sport.”

Meanwhile, Fifa has been urged to stage the Qatar 2022 World Cup in May and June, with the European Club Association arguing that games can be played at night without putting the health of players, supporters and officials at risk.