Real and core gamblers careless about the price of Bitcoin when they want to gamble, their only concern is if they have the bitcoins to gamble with. If they have bitcoins to fund their account with, they are good to go. The passive gamblers, that is people who gamble less often like me will be concerned about the price of bitcoins because we are not used to loosing to gambling and any bitcoin we loose during a time when bitcoin is performing well will hurt very much.