If you have asthma, and are wearing a mask while doing 50 pushups in 99% humidity/110 degrees F, you are likely to have a SERIOUS attack.
And for some of us, whether we can even DO 50 pushups is an open question.
On the other hand, I would happily pay $7 to not have to wear a mask on my vacation.
I can do half a pushup - the down stroke.