Think before you invest in casinos. Unless you know who owns them and their management never invest in any of the casinos. Else you would realize one day you are being scammed.
Correct, investing on casinos would be somehow profitable but if you decide to put money on them then its better to search to the most reputable one rather than investing to non famous sites which do sometimes shady which have a higher chance of being scammed same as you said.
I think some time ago there was someone who had to prove where the casino sites that provide the most benefits for investment and I think it already gives you a clear picture about which sites should you select. you just need to make sure that the site is reliable or not ?