Mike, you were of course quite right.
Aircrew had lockers in a large flying clothing locker room. Flying suits were serviced regularly and towels were provided for a post-flight shower before one went to the feeder for a post-flight meal and 'debrief' properly dressed in uniform.
Of course officers could not go shopping in uniform or otherwise. Shops shut at 5 and were usually closed from 1 to 2.15 when of course the officers were in the Mess having lunch. Tradesmen came to the Mess instead - Alkits, Moss Bros, City, Gieves - and you could order a suit or new uniform without meeting mere shop assistants.
Saturdays you were either working in the morning or free in civilian clothes if one insisted on going into town. Of course you may not have been able to get in to town as not everyone had their own car. Sunday shopping was unheard of and DIY was only for proper craftsmen.