I definitely wouldn't say shady - just unprofessional at times. It's like different business standards apply than do to the rest of the business world. It seems as if you need to accept that w/ a 'stoner's' mentality if you don't want to go on a rampage. Conversely, some show excellent customer service and business practices, and it is obvious they are thinking longer term.
I guess poor follow-through, inconsistency and disinterest in satisfying existing customers have been the biggest problems that I have seen