Average rent is more like $2K for a studio or 1br, not $3K. You're probably just looking at big apartment complexes. A majority of Boston's housing stock is made up of 3 unit buildings called triple deckers, which you'll find on Facebook, Craigslist etc. Anything new will ask for luxury prices.

That being said, passion exploitation and trust fund kids are a very real thing in the museum / nonprofit space. A lot of places pay poverty wages on the belief that you're doing what you love and should be "honored" to work for such a prestigious institution. And for every struggling college grad who asks for a survivable wage, there's three more trust fund kids who will gladly take that minimum wage entry level job and ask mommy and daddy for help with rent.