We welcome a new contributor, "B", who snapped them at the Asda end of Bedminster, and says "Probably parked there because of a terrorist shoplifter scare..."
That's certainly conceivable. We suspect the Basics Campaigners, who are #1 of about 47,100 results in Google's index of the phrase "campaign against sainsbury's". However, we don't think they plan to escalate their protest to Asda, architectural merits notwithstanding.
One thing all readers should remember is that the police can park where they want when on call, and they aren't people to upset. It is their right to park here. What is more frustrating to us is that we can't copy them. And why's that? Because it is illegal to impersonate a police officer, and that includes putting "POLICE" and "HEDDLU" on your white van and then expecting to park wherever you need to unload in Bristol, the South West, and Wales. Some people notice the ladder on top of the van and get suspicious, call the police, and then its serious problems. This is utterly unfair.
However, we have some news, something we will follow up next week: something you can legally put on your van so you can park on zig-zags by zebra and pedestrian crossings. Wait and see.