My answer to this is a resounding YES.
We are a business and although we like to give our customers a great service and great odds the bottom line is we have to make a profit. That’s not to say that everyone who backs a steamer is shut down; 26% of our active users are showing a profit and we have no plans to shut them down. As a rule of thumb if we feel long term we wouldn’t be able to beat a customer due to their betting patterns then we would consider restricting or closing that particular account.
It has never been easier for the punters to beat the odds with the exchanges betting to zero margin and numerous books competing so fiercely that its not uncommon to see them top the exchange prices. If a punter is constantly beating the odds then mathematically it would be a flawed business plan to continue taking the bets; after all you wouldn’t lay 11/10 on the spin of a coin!
Most customers take the news on the chin as its probably happened to them many times before but you still get the occasional incredulous punter who believes a bookmaker should never turn down a bet and he should be able to arb till his heart’s content!