When would they get stale, even if packaged in cello bags?

I think they can get hard, and putting in microwave would soften them, but really there is nothing in them(home made) to go bad for quite a long time. I can't say about boxed ones, except look for the expiration on the box

I was just thinking how long the krispies would stay fresh and crunchy, or do they get stale after some time?

I really have no idea how long they stay good for as I've never made a batch that wasn't completely consumed in less than 24 hours (often within an hour!).

I'd love to be able to make a bunch to dip into chocolate and store for that last minute tray to put together.