The damage/hit chart makes a lot of sense to me, just going by all the time I've logged into tf2. the knife is obviously high because it can do up to 450 damage and frequently does 100+ damage multiple times when a spy is really successful with backstabs. the sniper is a no-brainer too, with all the crit headshots/fully charged shots that kill virtually anything. the flamethrower does low damage/hit (plus not enough pyros close in even closer when they're burning someone) but racks up a ton of hits really fast. The minigun hovering between 10-15 damage/hit makes sense, too, because that's almost literally the amount of damage I've taken from it when I was able to test just a single bullet (not really test, I was just playing scout against a really crappy heavy who couldn't aim that well).
I was just trying to think of why rockets have such a huge gap over all the other weapons in the total damage chart. and what I think it is now is all the self-damage from soldiers helping medics building up uber. blowing up sentries helps too, but then stickies would probably be higher as well on the total damage chart. Especially since lately I swear I see 3-4 demomen on each team on nearly every server I play except the GAF one.