The betting firm that offered odds on former Sutton reserve goalkeeper Wayne Shaw eating a pie on camera during an FA Cup match has been fined £84,000.
The Gambling Commission said Tabcorp UK Limited, trading as Sun Bets, failed to properly manage the risks associated with offering 'novelty' bets.
It also became apparent Tabcorp allowed more than 100 self-excluded customers to open duplicate accounts and gamble.
Tabcorp has had its licence to offer gambling in Britain reviewed.
Shaw was shown eating a pie while standing by the substitutes' bench during Sutton's FA Cup fifth-round match against Arsenal last season.
Sun Bets, which sponsored the match, tweeted it had paid out a "five-figure sum" as that was one of its 'novelty' bets.
Shaw, 46, was investigated by the Football Association for potentially breaching betting rules and subsequently resigned from the Surrey-based non-league outfit.
He told BBC Radio 5 live his "world fell apart".
Shaw was charged with intentionally influencing a football betting market and improper conduct, and in September last year was fined £375 and banned for two months for breaching FA betting rules.
What has the Gambling Commission said?
Programme director Richard Watson said: "Vulnerable customers were able to gamble with Tabcorp UK, despite choosing to self-exclude. This is not acceptable. Gambling firms must ensure the systems they have in place are protecting their customers effectively.
"Novelty betting markets, such as the market Tabcorp UK offered on last year's FA Cup tie between Sutton United v Arsenal, may seem like a bit of fun but the consequences were serious - with the potential to encourage someone to commit a criminal act or breach a sports governing bodies' rules."
Tabcorp UK is to have new conditions attached to its gambling licence, and pay its fine to socially responsible causes.