This.
Advice on this is of course subject to the readers individual circumstances. However , for the younger folks an MBA isn't as big of a value add as it used to be for the previous generation. I think some commentary here is from a generation of guys who came in the workforce when even bachelors degrees were rare, and graduate degrees rarer.
Nowadays? I'll put it into perspective like this. A coworker's husband from an old job is getting a PhD. I'm actually outpacing his post-graduate earning potential in my current position despite having a relatively plebeian bachelors . By comparison, an analyst my current firm just hired has 15 years applied experience and a 2 year technical degree.
If one can get an MBA for free or nearasdammit with little opportunity cost to their career, go for it. I wouldn't rearrange my lifestyle to earn one at the expense of real world experience. A year working at Firm X even as an intern will go a lot further then a year spent in graduate school.
Down the road I'll use the remnant of my GI Bill on an MBA if time allows, but frankly by then I'll be too busy paying for more important stuff like a wife and kids.