Grower vs showers, what's going on?

You weigh yourself naked to remove weight variation of clothing. You shower at the gym because you have somewhere to be after the gym. You change your underwear because you just showered.

The walking about naked, brushing and shaving without a towel wrap I don’t get.

I change to underwear because by the end of my workout my gym shorts are sweaty and smelly.

Those guys weigh themselves naked because they are interested in the weight of their bodies, not the weight of their gym clothes.

ON EDIT:

Exhibitionism is the only thing I can come up with. Happily not much of that at my gym.

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