I know I’m going to hate saying this, but I do use butter and mayonnaise…
I don't see how anyone could be critical of that unless they don't like butter or mayonnaise. It's not like you are putting pureed tongue on your sandwiches (although some people might like that).
I am also curious if your mom's parents used real butter. I grew up in a margarine household and the first time I had real butter I was in love and I ran away with it. I never looked back and I would probably rather have my toast dry than put margarine on it, although I will use margarine for baking and there are a few high-end margarines I will eat. But no Blue Bonnet or Imperial except for baking.
Although, my foster-sister puts grape jelly on sausage and bacon and uses American style biscuits to make them into a sandwich. And some people like maple syrup on bacon or sausage. I don't really like grape jelly or maple syrup, though (Mrs T is probably going to faint now, LOL). I also don't care much for sweet stuff on meats. My mom used to glaze a ham in honey with pineapple and maraschino cherries on it on the holidays. Thank goodness she always made a turkey as well or I would have just been eating the side dishes.
We should have a poll on the buttered sandwich popularity. I would love to see how many people outside of the UK put butter on their sandwiches. Do our resident Canadians like it? How about Germany, France, Italy, Australia, New Zealand, etc.? I would guess that
Yorky probably does it as a transplanted Brit. And does everyone in the UK do this?
Is this going to start a new thread? It could if mods feel like it?