Bonus or not, seeing them squirm and fail to answer the question by repeatedly using throwaway phrases like "insider information" says everything you need to know.I like bookmarkers being grilled but she's on the wrong path. Bookies should be able to give and take away promotions depending on the customer. This is common in all commerce. It is, however, a different story banning customers from winning just because they're better than the books.
As someone on Twitter said, it's like Woolworths banning you from the shop because you bought too many things on sale