For now let's say it is, now pay for heat, electricity, and maybe a phone and you're at the $1000/mo figure I mentioned. That's "rent" in my book, however much it costs to live somewhere with the barest of necessities. And you'd never find a 3br in portsmouth for a grand, even in the shitiest of neighborhoods. Rooms for rent go for more than that in places where I've literally seen dead bodies by the front door. No fucking joke.
It has nothing to do with priorities. Food isn't a priority. A roof over your head isn't a priority. Notice I didn't include a car of any kind. $2000 a month in raw, not-able-to-be-lived-without necessities is easy to imagine. Take home pay for $40k a year is probably in the $2500 a month range, assuming that you live in NH with no income tax. That's precious little buffer.