Why am I getting emails for job opportunities not related to my background?

I’d decided to make my resume public again on three different career/job websites in hopes of landing employment in my field again. I’ve received a few responses from banking and insurance companies for management and sales positions, though my background is mostly mechanical and electrical, and I have no management, banking or sales experience. I’ve even received emails from recruiters asking me if I’d be interested in being a warehouse manager.

Are these messages simply automated, or are these recruiters that desperate?