+1

I do this occasionally in London, and never had any problems, except for quizzical looks, as it's an unexpected object in a shopping trolley.

However, if anyone did take me to task (and why should they, I'm obviously there to spend money) I'd asked them why it was ok to have small, defecating humans (aka babies) in the trolleys.

I've even done this at Whole Foods (yup, they have a few UK branches) which specifically says "no bikes", but security on the door just smiled as I loaded the bike into a trolley.

joan