I definitely don't know every person that is zapping them but I have a good idea who the regular zappers are and their typical zap amounts. It's less clear when they do really well and get near the top of the hot or top posts because then as you point out a lot of people just zap because they are on the main page. 

grayruby

It's funny: I often zap sports post because they usually are popular...don't think I've ever made a comment on one because sports really aren't my thing. Do you really know who is zapping them?

Scoresby

Would you like to know who zapped you?

For the most part I have a pretty good idea who is zapping me when I do sports posts. When I do other posts I don't always know but don't need to know and appreciate the zaps nonetheless. 