Well, the dancing and celebrations that the Mets embrace is a mere part of it. But Phillies GM Pat Gillick so much as admitted, although somewhat jokingly, that part of the reason that the Phils are in the World Series is that they, and the rest of the NL East, hate the Mets.
"If you want to know the best thing we had going for us this year, it was the fact that all the other teams in our division hated the Mets' guts. It started with Atlanta and all the hostility they had with the Mets through the years. Then Fredi Gonzalez left Bobby Cox to manage the Marlins and he didn't forget everything that went on between the Braves and Mets. Look what Florida did for us the past two years (beating the Mets two out of the three in each of the last series of the season to prevent them from making the postseason)! Washington doesn't like them very much either, and all those teams seemed to really get up for the Mets."
The lesson here: Take your hatred of the Mets and channel it into something positive like the rest of the NL East has. Heck, right now I'm sure a lot of Met fans hate their team right now ... or at least their bullpen. If there was a way that Met fans can channel their hate into doing positive things, who knows what can be accomplished. Better marriages, better jobs, better all around lives. For example, maybe if the people in charge of Wall Street hated the Mets a little more, the stock market wouldn't be in such disarray.