Well...I guess they could make the flight a nut free flight if such an situation arose but letting them board and clean away is their way of doing something. This way everyone around them can be free to eat away....

I remember going to Fenway Park and having great roof box seats. We were stopped by an attendant at row one who told us we had to dispose of our bags of expensive Fenway peanuts because, for that game, I was seated in a designated "nut free section". No signs before/when we bought the peanuts ..no notification when we bought the tickets. I didn't have any issues with the designation but I did have issues with the lack of prior notification. I haven't seen this section designated as such since that game but I'm sure there are other sections that have take its place ..maybe randomly....but I digress...sorry

Edit: I can find no direct reference to this new policy from AA...just news articles

Edit again: ..and why just AA (bite my tongue). Don't passengers eat on other airlines? AA doesn't serve nuts so that's not the issue