The crypto market is growing and its profitability is huge. The reason for so many exchanges that it focuses on many ICOS campaigns that offer multiple transactional exchanges and the future they will be profiting from selling and buying Altcoins and Bitcoin.
Everything does have advantage and the disadvantage. In a way its good to have lots of exchanges so there will be a competition among them all on which one will emerge as the best exchange so far, and apart from that another reason could be what you have just said.
But the reason you might not like it is because majority of them are owned by scammers, and that is a huge spoiler for legit exchanges that are still starting up new, cause everyone will now think they are also scammers. But whatever, I cant fall for all that.