I just spent my lunch break driving over to the office of the removal company that will be helping me move next week, to collect the load of cardboard boxes they're lending me (all part of the service). When I got there, I discovered that it's a perfectly ordinary-looking house on a residential street, without even a sign at the front mentioning the name of the company.
I spent five minutes staring at the front of the place trying to work out whether I'd got the address wrong or not, and then trying to figure out a good excuse if I rang the doorbell and found I had. (‘Sorry, I thought this was a removal company’ somehow doesn't sound too believable when you're looking at a house that gives no indication at all of being anything but an ordinary residential house!) Fortunately it did turn out to be the right place after all, so that was all right. I think they should put a sign up, though.
Another house three doors down from the removal company is running some other sort of business, which I could tell because it does have a sign up. So unless they're just tax-dodging, it doesn't seem to me that there's a fundamental problem.