I have incontinence, so I either wear diapers (still going to pee and defecate regardless), or I have access to the bathroom in time. If I wear diapers, there is going to be odor contamination in the area. It is bad for others, and for me, and their business too, I assume. Depends on the length of the trip; I try to limit fluid intake to zero before I go outside.
At peak season every year, O’Leary says something crazy like they are going to charge for the bathroom, or charge fat people extra, or get rid of arm rests, or have standing room only. The tabloids run the story, and always mention how cheap the flights are, including whatever the cheapest deal at the moment is.
It’s very, very obvious advertising. The tabloids go along with it because it makes people angry, which drives traffic.