Ok Inui, every fairly large tournament I can think of that does NOT include M2K, has had a MK on the top team, if not on most of the top teams. I've not seen a team in Texas that was missing a MK on it that also won. I've seen MK win with Snake, Wario, G&W, and even Diddy, but I have yet to see one of those characters win with another with ANYTHING CLOSE to the success MK has in teams. One of the only tournaments I can think of where two characters besides MK won for Texas was HOBO 15 (Me and Razer won Hobo 15 with mostly Wario/Snake), and a lot of good players were not there (Dojo, UTD Zac, IDK if Infinity was there or not). Every tournament Dphat and I have won we have done with MK and G&W/Wario/Diddy, not Marth and G&W/Wario/Diddy.
If I see a tournament where Chu/some other good person teams up and win without using MK, I'm gonna assume it's just because those guys are really good or because that area lacks MK's that can compete on their level, because at every other tournament of worth it seems that MK + some other character wins and places the most. Even if we count the legit tournaments you and Atomsk win without MK, it's outclassed by the legit tournaments that people besides Jason have won or taken top 3 placings with a MK on the team.
I'm not saying the MK's in your area are bad, but if they aren't winning or placing high in teams, they either need to work on their team work/have a more suitable partner, or they aren't as good as you + Atomsk or a non MK team. If you get a team with a good MK (closer to Teh Spammer/Tyrant/Dojo/DSF level than Shadow/DMbrandon/Ksizzle level) that also has good team work and maybe a good Wario or G&W (which your region lacks in Wario and G&W players), I bet they would win, aside from M2K teaming with like Ally or something haha.
Seriously though, MK is clearly the winningest/best placing character in doubles. G&W and Wario, while you can argue about them being better than MK in teams, still do not have the results that MK does in doubles, regardless of the reason (lack of Wario/G&W, MK being more popular, MK being easier to use in teams, etc).