It's really not that rare for smaller companies. Every two-bit contractor, small landlord who thinks he's smart because he put his properties in an LLC etc. undoubtedly violates the corporate/personal distinction by comingling funds. If an attorney wants to sue Joe The Local Incorporated Contractor, or Alice The Local Slumlord, first thing they're going to do is discovery through a bunch of corporate records- they'll easily find that the owner is mixing personal & corporate cash, credit cards, etc. Takes a good lawyer about 10 minutes