Because in case the site froze your account or you can't withdraw, some people here can help you with your problem.
Especially if you have done nothing wrong to flag down your account. Sites won't ruin their reputation from one unresolved issue.
That is, if you stick to reputable sites in the forum. But for new ones, try using small amount of money.
Controlling ourselves is actually the best solution for this. Heard some users actually blame some casinos when they tried to exclude themselves using the casino's exclusion program.
The reputation of the casino could still be affected no matter what because not all the people on the internet read the details of the gambler's protest. Most of them are just reading the thread title and judge by what is posted without looking if there is proof.
Yes, it is related to the casino reputation, but if the casino can investigate and do not find anything suspicious, I think the casino will not lose its reputation.