I've seen my fair share of questions that, while perhaps not side-splittingly funny, do contain at least some humorous/light-hearted content. One that comes to mind is about rewarding well-behaved inmates with free plastic surgery performed by medical students, presumably to boost prisoners' self esteem and to train future surgeons. That got a smile out of me when I first read it.
Again, it's not Mitch Hedberg, but relative to the usual boring, dense material on the LSAT I think it's safe to say the test makers do occasionally try to lighten the mood a bit.
RIP
I've noticed some things that I thought were funny, but I never thought it was intentional by LSAC. It'd be a lot cooler if it was!