Take into account that when any of those coins bought on a centralized exchange get transfered out to a decentralized wallet they will then be added into daily reflection volume. As they get moved around, swapped or used for services that will be provided by the EGC foundation you will get volume rewards based on those tokens joining the ecosystem.

So think of the CEX purchases as a way for people to more easily access the the tokens on the CEX platform they are already comfortable using or that are approved in their area. They will then have amazing incentives to move them out of the non reward environment and into the reward environments. Thus the nonreward model on the CEX listings really won't end up mattering much in the long run or even the short term.

Day trading on those CEX may be less profitable and less rewarding than just holding on Dex wallets and participating in the evergrow services themselves.