In my experience, most are checking the reputation of the casino itself before going to this RTP factor. It is like one of the secondary features that gamblers will check out on the casino. Because even if the RTP of the casino is much better than the other but they have existing allegations, are you going to play with them? I don't think so. But setting aside the reputation factor, if you are a regular player, I believe you will prefer better RTP. With promotions, sometimes they have conditions that you need to meet before you can join. But with better RTP, everyone can benefit.
We have here a gambling casino that has a bad reputation and even their participants have a negative warning under their profile, but they offered a lot of bonuses and RTP of course. So if you will know this issue, you will never even try to gamble there because of this issue. So for me, it always matters the reputation before anything else and I even suspect the casino that gives a higher RTP is a scam casino.
Nevertheless, people who are blind did see such issues and make noise when they get scammed.