I agree with the license part, but most of them try to run some various promotions here. First, they will pay, just to show off and gain the trust of the community. But very soon, they won't. They invested a little but was able to get some new players to their site.
About the license, shady and/or scam casinos probably aren't trying to get one is maybe because it needs a real identification as it will be regulated. Because of that, the community can find out who they are and file cases, or maybe chase them out.