Perhaps Mr. Irons could unwrap his items at home, then put each in a package or envelope and mail it to the offending company to let them dispose of it? Because doing this to innocent store clerks is not, as someone else noted, going to end with Lipton Tea saying "Oi, I will now stop selling my tea in a cardboard box because Mr. Irons keeps leaving it all at the store....."
Not that I believe mailing lots of discarded packaging to the offending companies will make a difference either. It just makes a wee bit more sense than dumping on store employees who have no influence over Heinz Ketchup or Monsanto Green Peas.
And yeah, I was wondering...does he open up the canned goods, too, and dump them into plastic bags or does he carry them home in his hands?