The 17-year-old, who was part of England's Under-17 squad that won the World Cup in the summer, spoke of several alleged incidents witnessed in competition for club and country.
In December, Liverpool lodged an official complaint to UEFA after Spartak Moscow defender Leonid Mironov was purported to have made a racist comment towards Brewster during a UEFA Youth League game.
Brewster allegedly also witnessed Wolverhampton Wanderers youngster Morgan Gibbs-White racially abused by a Spain player in the World Cup final meeting between the Three Lions and La Roja in October.
"Everyone stands behind the anti-racism banners. You have the adverts for Champions League games saying 'no to racism' in all the different languages. Idols of the game take part – but it still happens," Brewster told The Guardian.
"I'm thinking to myself: 'Well, I'm standing behind a banner but does it really stop them from saying it?'
"To be honest, I don't think there is any point. It needs more severe punishments. I don't think UEFA take this thing seriously. They don't really care. That is how it feels anyway, like it has been brushed under the carpet."
UEFA charged Mironov with racist behaviour and the case will be heard by the UEFA Control, Ethics and Disciplinary Body in January.