Mostly, casinos will never care as to how much you had lose, as long as they’re making profits, that’s good for them.
Of course they won't. The world is a cold place and we feed off of each other. Your lose is someone else's profit. The casinos don't have to care. They are there to offer you a service. If you want to use that service to lose $1, fine. If you want to lose half a million, even better. Responsible players understand what they are doing, and will find ways to limit their online gambling exposure when needed. The casino must accept the set account limits, otherwise they are in breach of their license (if they have one and it's a reputable one) and probably their own T&C and Responsible Gambling practices.