I buy tokens routinely, not many but most months unless I haven't used the ones I had.

My rule however - and it has been the same for many mmorpgs/freemiums over the years - is that I never spend more in a month than I'd spend on a pizza delivery.

I have 11 Tokens atm >.<

PS. I do 'waste' them on player renaming and silly experiments, but since it entertains me its not a waste....to me.