Actually, that frequently makes the charts look better for the one tribe than it otherwise would.
Let's say we have 5 tribes.
We'll call them A, B, C, D, and E.
A is warring B, the war is fairly close.
A is also nobling members of C, D, and E.
A vs. B graph would look fairly even.
A vs. B, C, D, E would look like A was dominating in a 4 vs. 1 despite them actually dominating 3 tribes that aren't banded together or working together, while fighting A.
Adding your "food" to the enemy side of charts is a frequent way to try and make your tribes stats appear better than they really are because sure it's more tribes you could lose villages to, but it's also more tribes that your nobles against show for.
EDIT:
Example:
Side 1:
Tribes: bAd
Side 2:
Tribes: PTT 2
Timeframe: Forever
Total conquers:
Side 1: 468
Side 2: 188
Difference: 280
Total conquers against opposite side:
Side 1: 4
Side 2: 0
Difference: 4
Points value of total conquers:
Side 1: 2,616,137
Side 2: 640,693
Difference: 1,975,444
Points value of total conquers against opposite side:
Side 1: 17,203
Side 2: 0
Difference: 17,203