Wait, how long has this been going on? Do most people really take showers every day? Most people I know (myself included) only do it when they get smelly/sweaty, which is roughly every day in the summer, every 1.5-2 days in the winter. Is this a US thing?
I guess this is one of those cultural things, and people just do it half because it's good sense and half because it's the custom.
South African here. I shower daily, no matter the season (as does everyone I know). Sometimes another quick shower just before bed on a hot day.
I just don't feel clean otherwise. Climate accounts for the seasons, but we do it in cold-ish Winters as well.
I think there's a distinction between hygiene and social/cultural 'etiquette'. I will always make sure I am very clean before meeting someone, casual or otherwise.
Just go out and walk, don't think "I have to walk because I need to lose weight", do it as an habit.
You don't think "I need to wash my teeth because I don't want them to rot", or shower every day because "I don't want to smell".
We probably could avoid washing and brushing our teeth for a day, without ill effects. But we do it every day because it's so ingrained in our daily routine that our day does not feel complete if we skip it.
It's much harder to break a rule than to break an exception, and routine is much more powerful than willpower.