I will start off by saying, I am not trying to be goady or suggest that people are wrong, I am just curious.
When I go to the gym there are always people who walk on the treadmills and I wonder why they don't walk outside instead. They are often young (it is in an area with a lot of student flats) with no obvious mobility issues, they are not using cars as they are walking too and from the gym. It is daytime, the weather is fine - not raining, not too hot or cold, the gym is not in a dodgy area or surrounded by roads clogged with traffic and pollution. They are not setting the treadmill to an incline or walking at a sustained brisk pace, but are generally ambling along on the flat.
The only reason I can think of is that it means they can watch videos or scroll on their phones without worrying about walking in dog shit or having to look up to cross roads or avoid other people but still get their step count up.
Am I missing something?