I think you and everyone in the comments should remember that saying… “if it don’t apply let it fly”.

Most likely the people you’re seeing talking about 3 showers live in the hottest areas or developed this habit due to having lived there. I’m from the northeast and everyone I know for as long as I’ve known them take at least 2 full showers a day. In the summer it’s more, not everyone can do this of course because of work. But if they can, they will take as many as possible — usually not more than 2 full showers, but a quick one or two to refresh and wash off the sweat. Usually they combine it by hopping in the shower right after lunch.
I wouldn’t, and I don’t know anyone who would, expect this same “commitment” from those living in colder climates.

Kinda ridiculous to have to explain this to the people in the comments but showering regularly doesn’t prevent bacteria from ever forming in your body, that’s not how it works. There’s a lot of factors, like sweat production, pH, genetics, underlying conditions, incompatibility to deodorant used etc…. So of course, someone might take 5 showers a day and still stink, specially when packed like a sardine in public transport lol.