You know, I love this forum, it's one of my favorites on Flyertalk for many reasons. Great comments on the etiquette point.

I used to be in outside sales so I've dined with my fair share of clients and I thought the leftovers advice was really weird. I used to always order something I knew I wouldn't spill on myself and that I wouldn't have to worry about having lefotvers with (can't go wrong with an entree salad) and I think he should have suggested something like this.