An 11-year-old girl was barred from claiming 'free fries' at McDonald's because of her age.
Mum Lynsey Mead said her daughter Amber was upset when she was allowed to purchase an adult meal but staff refused to let her redeem her winning promotional sticker.
Staff at McDonald's said that they could refuse her because she's under the age of 16, reports Hull Live.
Mum-of-one Lynsey from Willerby has called on McDonald's to give unbranded packaging to children who purchase food to stop promoting gambling.
She says it leaves children disappointed when they win but can't claim the prizes.
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"At the end of the day, it's a game, but it's encouraging gambling for young children," said Lynsey.
"My problem mainly is that you wouldn't sell a child a lottery ticket and then a scratch card, but not be able to scratch it off or claim the fortune."
Lynsey had allowed the schoolgirl to go with her friend to the Willerby branch of McDonald's on the shopping park at the weekend.
The pair had purchased their meals with their own saved-up pocket money and Amber's friend had peeled off an "instant win medium fries".
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However, when Amber went up to the counter to cash in the Monopoly token she was told she wasn't allowed the free food due to the fact she wasn't old enough.
"If I'd have been with her, I'm sure it would be fine, but McDonald's need to stop this promotion," said the mum-of-two.
"It probably would be better if McDonald's did ban her from going inside but all the kids love getting the stickers, don't they.
"But, on a serious note, I just think this promotion with the McDonald's stickers promotes gambling and promotes unhealthy eating.
"The larger meals have more stickers on them - so why wouldn't they want an adult meal, or a larger meal to get more stickers."
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McDonald's says the rules on its popular promotion are clear - and that is the reason Happy Meals do not include stickers on packaging.
However, Lynsey says children of Amber's age range want more than just a Happy Meal because they aren't "filling enough".
A spokeswoman for McDonald's said: "In accordance with relevant advertising regulations, our Monopoly promotion is unsuitable for those aged under 16.
"To avoid causing unnecessary disappointment as a result of this age-restriction for the promotion, it is clearly stated on all McDonald’s Monopoly promotional advertising, packaging and on our website."
Prizes on the monopoly promotion range from £100,000 as the top prize, along with cars, expensive tech, holidays and free food and meal vouchers.
