Ask HN: Is this legit or is it a sign of something sinister?

I'm a casual rust player and I was considering getting some custom skins for in-game items. One way to do that is via rust skin gambling sites. One very popular site offers incentives to deposit via crypto, paydash and gift cards. For every dollar I deposit into the site using those methods, I get an extra 35-40% value. Other deposit methods just get you face value. Is there a legit reason to do this or is it a sign of something sinister?