Someone actually exercising is being virtuous. Someone eating crisps is not being virtuous. It really is that simple.
As pp said, being virtuous isn't the aim here.
However, relieving the NHS is. A person eating a bag of crisps is in far less danger of using NHS resources right now.
The person doing box jumps, is in far more danger of having an accident and needing to go to hospital.
So its not really more virteous at all. Having their shoes on a bench, is more likely to spread germs.
If the person who sits down after them has health issues, that person is more likely to need the NHS from all the crap from the bottom of someone's shoes, rather because someone sat down eating crisps.
The person putting their shoes on a bench is spreading germs far more than someone eating crisps.
Being virteous isn't the aim. However, doing box jumps on a park bench isn't virteous at all.
Its a simple cases of you talking bollocks.