Wouldnt be appealing if it was always a loss, there is an implied cost to the gamble but it can always be a win or a loss.   Put simply a large amount gambled isnt any different rates of returns to a small amount gambled.   It can be quite true to win the gamble and gain the nicer free roll amount just because you gambled more, the risk to returns would be equal on small or large amount and the gain or loss in proportion thats all.
   If anything we could complain things are possibly easier if you have alot to gamble I guess but its also true the site wouldn't exist if people only bet half a cent so the incentives are justified.    Theres someone out there whose always got a positive gain and inversely some poor guy who never gets any luck.  The speculation is that on the average game and because a game has a 'cost' on average you can say the game isnt won but thats the theoretical average and some will gain on the gamble and also free rolls and other stuff like golden tickets, lucky them.  Telling people they cant win is more wrong then right imo