I would say that maybe 10% don't care about listings. Also some projects plan to do it but can't tell when will it happen. Anyway with Idex and Fordelta it's possible to sell almost every coin.
yes it's true if you want the best just etherdelta and idex but that doesn't have a good impact going forward if it's just a list there big projects are definitely looking for big exchanges and that requires time and commitment from the project maker.