You're ranting and raving at the wrong person, I don't tend to take my dogs into shops one dog HATES shopping (will just lie on the floor and yowl - which we discovered when she came along during the other dogs general public access socialisation trips) and the other only comes if I need him to work (assistance dog) which I don't always... and I don't shop in fucking Primark.
The risks are NOT low however, the risk that someone accuses your dog of scaring them is massive, a dog without its owner, just scaring someone, is almost certainly an offence under the control of dogs act/dangerous dogs act. Dogs are stolen and fenced around the country or as I say, ransomed back, or stolen and abused or stolen and used as puppy breeding machines.
It's also not just designer breeds that are stolen (but thats a nice bit of victim blaming there @NoSoapJustUseShowerGel ), any dog might be, the rise in general dog popularity and the average price of even a mutt being a few hundred quid has seen to that. Expensive breeds and obvious working dogs have always been a target for theives, there are just more dogs and more theives these days.
Taking dogs into shops that allow dogs in shops may be an imposition to you but that is put on you by the business themselves, not the owner - the shops WANT customers through the door. If that means allowing in dogs, thats what they're going to do. If you dislike that, make a bigger point of buying in person rather than online and tell shops you will avoid them if they continue allowing in non-assistance dogs.
I'd really rather they didn't personally as working an assistance dog in a shop, on the rare occasion I'd do that, is far harder when every dog and its mate is trying to jump on his head to 'say hello'.