You are right,it's investing, but the staking made by the site is shared between the investors. It has a risk, if someone wins big on the casino you could lose part of your investment. The site is holding half of the network, so isn't easy to lose in the long run.
I think that's understandable already because there has to be somewhere that site would get that win. Anyways, that site holding half of the network bothers me though. It's either they can take advantage or not.
Then you can install your own clam node and start by yourself with zero risk. For that, you need a PC connected 24/7 and some skills to configure the staking. But should be possible for all.
It maybe an easy setup but I'm not sure if it's profitable in my end. Electricity here in my place is expensive. On a VPS, I'm not sure if it's allowed or even possible. I don't know but thanks for the ideas.