Does not suprise me in the least I am afraid, but rather like yourself, I would not have anything to do with it.
When clients are only concerned about price, I am afraid things like this are going to happen. The cleaning industry as a whole really does not help themselves when things like this happen, we all have costs, these must be covered, when somebody goes down this route, you have to wonder and worry about their other shady practices in the really important stuff, such as employment legislation and Health & Safety etc, best off out of it imho, regards.