You do realise those extra 10 crystals is just to goad you into spending money. Just look at the purchase offers. $4.99 for 20 shards. (1 pull, still 10 left). $19.99 for 80 shards. (4 pulls, still 10 left). Oh but wait. For $49.99 I can get 210 shards.... I can finally make use of those extra 10 "free" shards. Just gotta pay $49.99. So again, you missed my point. It's great they put this event in for the chance for something. Just don't blow smoke up my ass with the extra "free" 10. Oh, and to answer your question. Yes, I would rather NOT get the extra 10. I'm not a whale, so they are just going to sit and rot.
The extra will roll over to the next event, no rotting. These hamburgers freeze well for future consumption.