Or security guards, or military. I've been doing 12 hour shifts for the last 10 years. Someone give them a straw.
Right there with you - closing on 15 years of 12-hour rotating shifts (days one week, nights the next - heck, I'm doing a 24-hour turnaround for open-shift coverage on Friday, rolling from days M-Th to nights Friday and Saturday!), and that's on top of 6 years in the Navy before that. Did probably a couple of years worth of five-and-dimes while on the TR. Someone complaining about 12-hour STATIC shifts? Cry me a freakin' river.
Undermanned, you say? No stranger to that either. Job I'm at has been at ~90% manning, on average, since before I got here; we've had about 1.5 years of nominally-full manning, ~2 being 1 down, and close to 3 years of being 2-3 people down in a 12 man department, since I got here. Job I was at for 8.5 years prior to this one was also typically undermanned, though less so than my current one - probably ~95% or so on average.
Their complaints find me strangely unmoved.