Yes, online slots casinos are trustworthy as long as you know where to go. The vast majority of online casinos are completely safe places where you can play and earn real money. However, there are some scam sites out there too. That's why it's important to understand the signs of a trustworthy casino site.
The odds of online casino games favor the house, but not so much that you will ever feel cheated if you are playing a fair game, of course. It is possible for an online casino developer to lower the RTP in order to lower your chances of winning money.