A high roller, also referred to as a whale, is a gambler who wagers large amounts of money. High rollers often receive lavish "comps" from casinos to lure them. Answer 1 of How much do you have to gamble for casinos to consider you a high roller and start comping everything for you? 50 grand?. It's a.m., Las Vegas time, and you've been hammering at the casino all day and all night. Blackjacks drop as if you have control over the.