The house always wins.
So, my husband and I were drawn in by the 99 cent margaritas. We ordered 2... handed over a $10 bill... and were give $3 in change. I immediately informed the bartender of the error. He checked the cash register and said that it wasn't possible because if we gave him a $10 and he gave change for a $5, OBVIOUSLY the $10 bill would be in the $5 slot. Right.
He then offered to call surveilance. We said, "Please do." After waiting for about 15 minutes, the bartender returned, held up his hands with a fake apologetic look and said, "Sorry! Surveilance said they saw a 5."
So... if you choose to go to Fremont Hotel and Casino, make sure you have the right change or the 99 cent margarita's end up costing $4.