*E.g. your grandfather is Joe Jamail
For other schools on your list it's a different story. They certainly have a better chance, perhaps even a good chance, of getting the BigLaw job golden ring than most law graduates. But in my observation that's a bit of poisoned chalice. It pays well but the work is mostly tedious, the hours are very very long -- with no slowdown as your career advances -- and the atmosphere is extremely stressful.
There are some good public interest jobs for people who for whatever reason aren't money driven (usually because they have money already!) but the competition is fierce even for Harvard and Stanford grads because of all the burned out BigLaw associates looking to get out. Although the jobs are often interesting and sometimes fulfilling, they almost invariably require long hours. Almost all legal jobs do.
And I actually think paying for certain masters degrees, for example in computer science or engineering, is a better financial investment than paying for most law schools, particularly in the present environment.
I do agree that one should not pay anything for a PhD.
So, the master's is potentially costing you triple - you're paying for it, you're not getting paid, your value as an employee isn't going up as much as someone who is working.
If you can't find a sponsor to pay for a master's degree, then I would assume that nobody values you having that master's degree.
For how long is this true? I mean, at this point, I have "more than a decade" of experience - and, considering, I think I'm likely to say 'more than a decade' even when I have two or three decades of experience; no reason to point out that you are old.
On the other hand, people leave their degree on their resume forever.
My point here is that years of experience seem to have, ah, a diminishing marginal return.
(that said, I'm almost certain that you are correct for the first five years of your career... /if/ you can get a good job without a degree and without experience, which in my very relevant experience, depends a whole lot on the shape of the job market at the time.)
Actually, as someone without a degree... the 'perishability' of my credentials is something I think about often. I mean, i wrote a book, [1] which is a pretty strong credential, but will one obsolete book mark me as 'middle class' 20 years from now? probably not. A masters degree would. (Now, would that masters, if it was fallow for a decade or two, get me a job? probably not by itself. But, my impression is that it keeps it's value as a credential longer than, say, my book, and certainly longer than work experience.)
Considering putting cash under your mattress is a better investment than paying for law school, yes, you are technically correct.
However, I don't know how "worth it" financially even a master's degree in Computer Science is. At best, I feel like it's break even in most cases: the year or two you spend getting the degree might be better spent on the job, especially if you have a decent mentor.
In one case, a guy I mentored directly out of undergraduate ended up going back and getting his master's. I think he'd say that it made him feel more confident with certain concepts, but then, I picked up the equivalent information in the course of my 10-year career with only an undergraduate degree. Any reasonably curious programmer would. It certainly did not make a difference in his income.
As for PhDs, I have never hired one. They seem to universally have an inability to think concretely or in a step-by-step manner. They have the skill set of a junior developer but expect the salary of a senior developer (at least). Ultimately, I can only imagine hiring one if they had significant experience in a very specific area that is difficult to hire for.
Could you elaborate on why you think that "PhDs have an inability to think"? If anything, I would have thought that a PhD will be extremely methodology and think through every step (after all, that is what you are supposed to do in a PhD).
Maybe. You can't just compare the outcomes of people with these degrees, though, you have to consider their prospects going in. Typically, someone who applies to cs or engineering already has a closely related undergraduate degree.
A history major who attends an elite law school probably does see a pretty dramatic jump in salary prospects. A computer science major who gets an MS? Probably a bump, but the undergraduate degree is pretty employable already.
[1] Some Ph.D. programs routinely award Master's on the way to the doctorate; I'm talking about terminal Master's.