It's called sillage. Those people probably know that they overdid it from the look/reactions of others, mistakes happen. Another thing people might not like about smelling perfume is that when the scent is the same with somebody else's, generally people don't wear perfume where I live, so I can get by with a scent that might be too popular elsewhere, I spray generously, it's called wearing perfume like French.

I understand that it's something one needs to wear with some considerations for others. If it still smells good though, even if it's overpowering your senses, please don't forget to compliment the wearer, then complain.

It's like body odor, right? Who am I to tell someone that the person stinks too much and should wear deodorant and how much. Some don't believe in the safety of deodorant products and in close quarters, I may not be able to tolerate the smell too long. The wearer don't know the sensitivity of other noses around that person, it's just a novice mistake or the person could be insecure, even a bit OCD about he/her scent of the day. Depending on the skin condition/parts and the temperature, perfume projects differently, even smells different. I'd also consider the possibility that the person may have needed an extra uplifiting magic that goes with what the person chose to wear, he/she could be masking something, like emotional difficulties.

Also some people feel naked without wearing perfume at all, it's a part of their wardrobe, and it takes finesse to execute it with perfection.

By the way, thanks for the idea for what to wear today, Dior Homme, it has a beauty shop smell, they call it lipstick note, are they almost the same thing? I don't recommend this for anyone, you'd have better luck trying flankers of DH. Intense, or vintage Intense which I never tried have good reputations.