When my DC was having his appendix out,I arrived from work one day and was in uniform,and the doctors were doing a ward round,they "assumed" I was just one of the staff and totally ignored me,I had to speak up and explain I was "mum".
I would never call an elderly person by their first name unless invited to do so,I trained when everyone was referred to as Mr or Mrs or Sir etc.
I personally feel that standards have slipped when "Sister" on the ward is called by her first name etc. Casual terms, casual attitudes,IMO.
But as a Mum I am proud to be called that.That is my "Status" and I want HCP to recognise that.I don't want my DC to be frightened by an officious nurse or doctor,a "casual" manner with a informal term makes me feel more at ease to ask questions.
I just don't agree its condescending.I'm very proud to be a Mum,and as such don't mind people acknowleding that.If I'm in the minority,then so be it.
By the way,we have done quite a few anon. surveys.While some people may not openly object to this,I'm sure they wouldn't say that they feel their nurse is approachable and eficient,if they were so grossly offended.