I looked into entering the paid event as a product_class in the table but unfortunately it created a dummy content type which was of no use and distracted from the actual event content type. It is true that I have removed weight from the event product, but it certainly has a price and that is used as determination of it being a product (test for display of product form in event content type node edit form).

Anyway, I've added the relevent code where it is needed for this module and will keep a record and put it in the uc_event README.txt for the sake of users. And we'll see what happens.