What are those small usually black packs that men are carrying on their shoulder? (Not man purses)?

I have seen some men carry a black bag the size of a waist pack on their shoulder into places like the mall or Target. So now I have been looking for a bag like this. The only things I have come across are waist packs, digital camera cases and lunch cases. Now I am assuming that they are not packing a lunch to go to the store nor is it a photo capturing opportunity and I know they are not man purses. These are sporty bags with zipper closure. My only conclusion is that they are waist packs. What is your take?

These are way smaller than handbags/messenger bags and they are not purses. They are sporty with velcro or zipper closure, none of that leather and buckle stuff.

Shoulder packs.

hand bags or purses