Turkey has in interest in finding agreement on more permissive visa requirements, it wants to be recognized as a safe country of origin and it wants to finally return to constructive EU accession negotiations. We Europeans decide all of those things together.
Refugees cost us money too when they come to us. If we improve their living conditions in Turkey, we create an incentive for them to stay there and not to place their fates in the hands of smugglers.
Turkey is doing an enormous amount in the refugee question, but it can't continue to pay for everything by itself. That is why we have to talk to Turkey about money.