I never really put attention to trustpilot as most of the times people will only post when they have a negative experience. Something is also fishy when you just read positive reviews also. Some complaints don't make sense also like the first ones. That guy is talking about buying 2500 tokens (I suppose FUN tokens for the premium membership) and than claims to have lost over 2000$ while buying 2500 tokens would only cost 18-19$ lol. To assure all the new members on here also, this is one of the most legit sites out there and I, together with a lot of players, can only recommend it.
Well, we never can just conclude and push things away just like that, we all know that not everyone is good with English, we know that some can only manage to express themselves in the best way they understand and can, but not in the best way that would be generally understood.
Maybe, the guy didn't mean he lost $2000 buying Fun token, maybe he meant he lost that money playing on freebitco after upgrading to a premium member, the mentality he probably have is this, since he's a premium member or user rather, he shouldn't have lost that much

.
Some probably do not understand that, becoming a premium member is not an automatic immunity to gambling loses.
I have seen plenty of people like that, I have seen people who ended up basically saying "how can I lose 10+ times in a row on 50%!!!! it's rigged!!" and so forth. Statistics and possibilities are not the strong suit of someone who doesn't know much about math and lost a lot of money.
When you combine those two, you get yourself someone who doesn't understand how any of this works, and complains all around the online world about the most legit websites. The important thing is, they are legit and have been legit for a decade now and this won't change anytime soon, maybe people may come out once in a while and complain, but the general consensus will always be freebitco.in being good.