One of the older male clerks at the main post office (back when we had a main post office) used to call me "dear." I didn't mind, as he was always polite and genuinely tried to be helpful.
In most online situations, "dear" is a term of disrespect, condescension, and not that I intend to reveal my YT username, but if I ever address anyone there as "dear" it's because I think they have said something monumentally stupid.
"Sweetie" is a nickname I had for one of my cats. I've never used it to any human or any other pet I've had. It just seemed to fit this one particular cat, as he really was a sweetie.
"Hon" is something I find a bit annoying, but don't make an issue of it.
The really bizarre one, though, is "Love." One of the guys in my SCA group started using that one, and his wife picked it up, too. It's downright weird to be called "love" by someone who you know doesn't like you, you don't like them (much), and it just seems so hypocritical.
It's when officious strangers or people in authority trot out these words, or just assume that first names are okay, that I get really riled. I'm honestly not offended if someone calls me "ma'am" and there have been times when I've had to actually explain that some words and names are okay if we're either related or very good friends. But if we're neither of those, formality is what I prefer.