I think the question can be asked from the other way. It depends on which exchange tokens are listed and traded. As for almost all tokens based on ETH, they can be immediately traded on etherdelta by contract address. And you don't need to undergo any verification process on etherdelta, which is a good thing is some cases. On the other hand, when token is listed on a big exchange, some may find it as a better option, since there are much more people ready for trading and volumes are higher.