Steve Walker wrote:

Nope. Any car parks, roads, etc. that the public have access to can now be
considered part of the highway for road traffic enforcement purposes.
Anyone sensibly using an empty car park for a bit of skid pan practice can
be done for dangerous driving or any other such offence. People have also
been done for not being insured when having a go of other peoples vehicles
in car parks or for not stopping at a pedestrian crossing in one.

But supermarket car parks don't have pedestrian crossings. They might
have white stripes painted across a part of them, but that does not
constitute a valid pedestrian crossing. It only mimics a zebra crossing.
No Belisha beacons involved.

Dave