Here's the section that I think answers your question:
> Who’s paying for this? Well, again, if we look at government numbers, it looks like it’s friends and family, meaning girlfriends, other family members, and Uncle Sam. Disability insurance programs pay some benefits for more than half of these unworking men, it seems. Disability benefits do not provide a princely income, let’s be clear about that, but they do allow for an alternative to life in the working world, which is exactly the opposite of the original, and I think quite noble, intention of disability programs, which is to provide for people who couldn’t take care of themselves, couldn’t work.