My mother always addressed letters to Ms E Bearhug - well, certainly since I went to university. I didn't receive many letters from her before then to know if she did it before, as we didn't usually write to each other while living in the same house... So I've never seen it as weird.
I do notice that I seem to have reached an age that when asked for a name, people seem to default to, "It's Mrs..." Although I've been dealing with one of our vendors over the last couple of weeks, and for the same problem ticket, I've mostly been addressed as Ms Bearhug, but also Mrs Bearhug, and twice as Mr Bearhug. Most of this after the first Mr occurrence, where I pointed out that I preferred not to use any title, and just addressing me as Emma was fine, but if they must use a title, then it's Ms.
For most occasions, even my sex isn't relevant, let alone my marital status. Apparently I can't have a bank account without a title - now, I can understand they might need to know whether I'm male or female for ID purposes, but this could be handled by a field marking M or F, not by a title. I am allowed a title-free bank card, though.
A friend at uni once had an absolute go at me for addressing a card to Mr & Mrs Smith - well, I knew she was Jane Smith, and he'd only ever been introduced as John, so I had no way of knowing he was John Brown rather than John Smith. Obviously, had I known, I would have addressed it differently. To this day (20 years on), I have no idea what his surname actually was, because she never actually imparted that information. I do try to address people as they prefer, but I do need to be told preferences and related information to do so.
And I've ranted many times about poor programming that means so many online forms won't let you have the option of no title, even if that's what you prefer.