I'm sure there are a fair amount of players that don't feel others deserve the XP and maybe some are trying to get as high as they can on the leaderboards, but I feel it's mostly just ignorance.

Many players just don't realize that they will get the exact same amount of XP whether they confirm their own kill or a teammate does.

That's exactally what I thought. You are put on a team. Every tag you see laying around needs to be collected, so who cares who gets it? I had some guys bitching at me DON"T PICK UP THE TAGS! You people who play on a team, but are playing only for yourselves, should stick with something that lets you be stingy, arrogent, and self oriented. If you play on a team, shut up and be part of the team.

Many people don't realize that in order for a confirm to count towards an Elite operation one must actually collect the tag.