Interesting two sides of the coin, here's my 10cents

I nearly always reuse the styrofoam, fortunately most of the cardboard boxes (here in Oz) only have a catalogue number on so that's not an issue.
If I was to dispose of the stuff I'd need a garbage collection every day ($10 a time). It ususally takes up less large boxes when they can be stacked on top of one another.

But really it's all about how you "SELL" this to the customer, I don't say hey how would you like to get rid of my garbage for me!.

But I've packaged these in foam so they won't get damaged, and no-one can sneak peek the names until you display them.
EVERY time I get a "thanks very much that's thoughtful of you!".....

Most of my customers are repeats so they trust my engraving and don't bother to check at pickup.

regards Clive.