I've noticed something.

Within all the fans of all the couples, especially the DxC fans, I've seen more care about the couples than the whole show.
Some people only watch the parts of the show with the moments of these couples in it, then they don't care about the rest. Not saying everyone, but I've made my observations.
I'm going to prescribe a few episodes of shows I suggest you watch for a lesson

Phineas and Ferb "Nerds Of A Feather"

iCarly "iStart A Fanwar"

Both of these episodes are about warring fandoms.

Nerds Of A Feather shows two groups fighting over two movies: Space Adventures and Stumbleberry Finkbat. The "Finkies" and "Speckies" go to war over this. Phineas and Ferb use their speical effects software to create a hologram monster that resembles a large, mutant, cyborg bunny. The two fandoms work together to defeat it.

iStart A Fanwar is about an iCarly conference at Webicon, an internet convention. The fans at the conference are on two different sides: The "Creddies", who like Carly and Freddie as a couple, and the "Seddies", who want Sam and Freddie as a couple. These fandoms end up in a verbal AND physical war (all inside the conference hall) over the couples. The iCarly gang tries hard to stop them, but in the end all they accomplish is having a bunch of angry Creddie fans attack Carly's crush, Adam, who came to the meeting to see Carly.

We can learn from these, no?