And the player is supposed pay attention to this ?! 
I didn't say that...There is a bit of a difference here that they don't make the max bet amount known and you kinda have to figure it out by finding the max win amount and dividing it by whatever the multiplier is. Combined with the fact that they would happily collect a $5000 loss for a $2000 max win.
I agree that it was indeed poor implemented. As for collecting overmax losses, has there been a verified instance where this actually happened? If so, has the user made a claim for the erroneous overmax bet amount to be refunded? If so, was it denied? If Yes, Yes and Yes... then I would definitely agree that the Casino is in the wrong and any overmax bet amounts should be refunded.Quote
I can't think of a good excuse for an online casino to not enforce the max bet upfront. I'd be more concerned if they turned my webcam on to track me down 
Me neither... but I try not to attribute to malice that which can be explained by incompetence... To me, this looks like a poorly implemented system (followed by bad customer service, insofar that it was explained and handled poorly)... as opposed to out and out deception on behalf of the casino."we like to let players play how they like" is not a great explanation.
If it was, I'd like to point out that "I like to play with 0.00000001 sat bets with 9999999999999x payout at 99% chance" #ICanHazBetNow? 
The error allowing players to bet over a max win is supposed to be fixed now.
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If it is fixed great, they won't have the same issue pop up.
^-- This. I hope they at least gave you a "bug bounty" for your time and hassle....
If it is fixed great, they won't have the same issue pop up.