As a business owner I also feel that for someone to come in and take pictures would feel a bit violating. We've actually had competitors come in and take pictures of our store layout in the past in order to copy.

If you're trying to get their interest with a custom poster relevant to their business, why not use stock footage? For example, I am pretty sure there are plenty of hookah images you can find for free or really cheap and then making it into a poster would give you the same results.