I would still prefer to play with those legit casino gambling than those casino gambling that offers bonuses but once you play it you will regret trying it. Better to play with those legit casino gambling without something to offer on you but you will assure yourself that you will receive your prizes or reward once you win the game.
Almost all casinos started with neutral reputation, in this case no one knows whether the site is legit or not. It is also not the main idea of this topic, as it is about what welcome bonus that may attract you as a gambler. Just imagine that all sites are new, no one is considered as legit so what welcome bonus that may make you to join and play?
I understand he tried to mean with old and reputed houses and not about new houses. Because, I usually do that exactly. Whatever offer a new casino will be offering, I do not mind. Because, I am not ready to risk with new/unknown houses. It may be due to the reason of, suppose if I manage to make big profits out of those welcome bonus and if that house is a scam one, then all my efforts will go in vain.
So, not showing interest on any kind of welcome bonus from a new house is just a precautionary measurement from my side to make sure that I am always gambling with the possibility of withdrawing to my personal wallet. Recently one new house offered up to 10 deogecoins as a sign up bonus. I have availed and I enjoyed the game by testing the new house because I have prepared myself not to go for up to withdrawing level (because of it was only dogecoins) but decided to enjoy the game by experiencing all new graphics.