Equally, it's one day a year to eat a ready made sandwich when all the sandwiches on all of the other 364 days are homemade ones.
Fun tangential fact. Delia Smith's husband used to play for a local cricket club. She used to take her turn with a number of other wives on the rota to make the teas (if you aren't familiar with them, a cricket tea is essentially like an afternoon tea for both the home and away team players, and is a Whole Thing that clubs and leagues take very seriously indeed). When it was her turn, she made all the cakes herself but would buy the sandwiches from M&S, because she reasoned it was the least important and interesting part of a cricket tea. Her teas were legendary and all of the league officials would try to time their visits to that particular club for when it was her turn 😆
So I hope you can smile that you're in good company with Delia Smith 🙂
I don't think putting together an afternoon tea from entirely shop bought things is a shoddy effort. My mum has sent me afternoon teas (from a company) through the post, and she lives 10 minutes away from me 😄I've taken her out to afternoon tea at the garden centre etc. This year me and my DD have put together a gift bag of a few things that her Nanny likes to take to her tomorrow, along with a beautiful bunch of flowers from Aldi. I really hope she doesn't secretly think we are being low effort or lazy because it's all bought and none of it home made this year (it's pot luck if I or DD have inspiration and the time to make something.) My mum values home made things very much (as do I), but we don't worry if nothing is homemade on any given occasion.
I really do think this is a non-issue. if I bought somebody M&S Sandwiches as part of an afternoon tea, I would think I was doing something nice for that person, a bit posh and fancier for them than what I would put inside a sandwich if I was making it myself. They probably thought that you always making them yourself was exactly the reason why you might like posh shop bought ones for a special occasion. They misjudged, but please don't think it's laziness on their behalf, I would put good money on the intention being that it would be a nice treat for you, not laziness on their behalf.
I'm also strongly of Delia's opinion that the sandwiches are the least interesting thing in an afternoon tea anyway, so even though you don't really like ready made sandwiches, I don't see why them not being homemade should negatively impact your enjoyment of the whole tea. I think whatever fillings they have bought you, they're still likely to be more interesting than the standard ham, egg mayo, and cream cheese and cucumber that our favourite restaurant puts on their delicious afternoon teas. As I say, least interesting part of the tea!