There's a few places in my neck of the woods which conducts business this way. Almost all of their business is word of mouth from what I can tell. They do great work, however. It is unusual, and the reality is that most likely they are avoiding taxes. Personally, it's on them and I don't have a dog in the fight. Now, it could be an employee skimming money off the top. That I do have a problem with since the employee is taking no risk in the enterprise, but he's getting the reward. It's a crapshoot unless you have a relationship with the company. Many companies follow the traditional route of receipt, et cet., and do crappy service and you generally have no recourse since who is going to sue over $100 bucks or so ?