He drove the hearse for a pet cemetary, so it wasn't too depressing. He was also a hoarder who lived among piles of tottering filth, and used a black trash-bag for a tolet.

This answered the prayers of many tween girls: it would be great if Bobby had his own TV show, but it would be even better if he lived with a psychologically damaged hearse driver!

Or perhaps Sherman himself asked for this character. Not to say he needed a really stark contrast to make himself even more attractive to young girls, but every bit helped.