One of the casinos where I gamble have gone totally overboard with their marketing campaigns. They are spending millions of dollars on marketing and to fund this, they introduced several projects to increase traffic to their site. Now, I am not going to say which site it is.... but I guess a lot of people play there.

The site is great ....but the
gambling experience has deteriorated... because the RTP has been nerf'ed to hell and gone to pay for these projects.
Now my question is this... do you prefer that a casino offer loads of promotions and campaigns and sponsorships and sacrifice RTP in favor of that.... or will you rather have a decent gambling experience with a better RTP?
Let's discuss...

I think both are needed. Even those perfect casinos are going heavy on promotions and marketing campaigns. If you have a good product but nobody knows about its existence, what good is it? Good products may sell itself but promotions and marketing campaigns multiply those sells by 10 or 100. Marketing&Promotions usually are the most important thing when you are selling a service/product. Almost as important as the product itself. Sometimes even more important.