Sure, they (the exchange) benefit from shitcoin because the list costs are quite large, so I think the exchange does not think about the quality of the project and only think about profits. It's very rare for a really tight exchange to list a token/coin, as far as I know is that Binance can't list all the projects there.
depend on the exchange there are exchange looking only for a quality project even you have funds for listing they will double check if you will have enough liquidity to list in thier exchange.
Mostly small and unknown exchange only accepting shitcoins because of listing fees.
Yes, all of the exchanges fee are not same. Shit exchanges asking very low fees and this advantages will take scammer. Big exchanges first condition is project analysis, if it seems good quality and team is real after many justified than fee and other agreement will be happen.
Latoken,P2PB2B,Exrates.io,Fatbtc,VinDax,Dcoin these are so lower scheme exchanges and enough to destroy good projects.