Student loans don't discharge in bankruptcy. Also, the odds are not decent of landing a "sweet job that lets you pay [loans] off much more easily and have plenty of money to spare." Take a look at the bimodal distribution for starting lawyer salaries.[1] In 2011, less than 6% of graduates got jobs at large law firms paying $160k.[2] I don't know current attrition rate stats, but generally most of the entry-level class at a large firm is gone within 5-7 years.[3]

It sounds like the people you know may have gotten lucky pursuing a high-risk gamble, whether they knew it or not.

[1] http://insidethelawschoolscam.blogspot.com/2012/10/five-stag...

[2] http://lawprofessors.typepad.com/legalwhiteboard/2012/07/a-p...

[3] http://www.law.com/jsp/llf/PubArticleLLF.jsp?id=119494824709...