Online casinos have come a long way in the past decade or so. During the early stages, there were some online casinos that were set up by dubious entrepreneurs that used to cheat. They had faulty routines that did not pay back the amount that they should have. They were the so-called cheats.
Nowadays professional gambling houses run most of the free online casinos and they play fair and square. They know that if they cheat, they will end up being the losers. Most of them have scripts that pay back a certain amount of prizes of the money that is input. It is well known to these online casinos that they cannot last for long if they cheat.