I don't see any issue with reusing bubble mailers as long as you secure it the best you can if there are rips from previous use. I take packaging tape and completely cover the mailer and I haven't had any issues to date. I've received chips in brand new mailers and the chips is just floating around loose and the mailer is just closed with the glue strip, I think those chips have a better chance of being lost. I also take old mailers, cut them up, wrap chips in the mailers, put them in a regular envelope and completely tape the envelope with packaging tape.