See my other comment regarding the UK, where serving lawyers actually earn less than the national average. So yes, it's a bit puzzling. On the other hand, a law degree is a bit of a "I don't know what I'm going to do but this will at least give me a firm backing" type of degree.
You can take a law degree and go into any number of professions such as jobs in the police, human resources, journalism, areas of finance, all kinds of compliance roles and oversight or strategic positions in-house in companies etc. Basically you can treat being a qualified lawyer as having proven that you're able to work hard, learn fast and pay excellent attention to detail, which is often just as valuable or more as domain specific skills.
E.g. my ex recently went from one of the Magic Circle firms as a 2 year post qualification lawyer (UK system for solicitors - for barristers (litigators) it's slightly different - == 3 year law degree, 2 years training contract and passing the legal practice course; the latter can be done as part of/during training, especially if you get a contract with a top firm) to a director-level human resources position at a major bank on the basis of being a qualified solicitor with some lower level HR experience years ago, before her degree. Her legal training is by far the most relevant to the role vs. HR experience, given all the regulatory/compliance issues and general legal issues an investment banks HR department has to deal with.
But certainly, going into law to work in a law-firm is far from lucrative for most people.
(not that the overall cost is much lower in the UK,though: the law degree is a first degree, and costs the same as any typical first degree, and if you get a training contract the training is paid and many firms will then cover the cost of the legal practice course as well; even if you don't get a training contract before your LPC, it's possible to do the LPC for about GBP 5k I think)
