Hello,
When you give these treat whats the quantity of them , if its only a scrap it shoulndt affect eating habits, however if its enough to fill up on then I can understand why the cats being like this..

I would keep out some dry food (as it doesn't spoil so quickly) and then put wet food out as normal. perhaps in smaller portions.

Only leave it out for an hour or so at a time!

Sorry i'm not much help.... I've been blessed with unfussy cats