Do they hatch into something? Do they contain special prizes? or are they just collectors items - for display only?

Yeah, I thought i might ask before i spend my tokens :D

Nope, just foods. :)

darn! I was hoping they were something other than that xP anyway... thanks! Now I now what to avoid or prioritize last xD

You could always get a Vesnali Balloon Gift. They give one item out of three.

awesome! i'll try that :D

Pink Sparkly Eggs give items.