The go seems to be these days, rather than party bags, to have a Piniata and give the kids an empty party bag and they fill it up with what comes out of the piniata, you can put a combination of lollies and little party bag toys in them. That way, you can have just plain paper bags, decorated with stickers on hand for any unexpected guests.
... oh Heather that's just what i did for the first time for my DD's 4th b'day party this year, i picked up a pinata marked down at Kmart a couple of years before but found the kids were too young for it back then but this year at 4 it was perfect, they were all fine with being blind folded too ... yep did just what you suggested Heather in handing the kids a party bag to fill, in fact they were so excited they were all stuffing in their party bags the shredded cellophane i popped in the pinata for it to look more exciting when it busted open

I made sure all the lollies in the pinata were in wrappers so when they hit the ground (even though it was a clean carpet in the garage where the party was held). The shop Sam's Warehouse have a bag of lolly hamburgers, hot dogs, pizza's & icecreams for only $1 for a bag of 'em, the kids especially loved the gold foil choc coins from the Reject Shop