[Mr. Mojo]

is that because the Jets played at Shea for so long?

That'd be my guess. ....plus both the Mets and the Jets are perceived as "blue collar" teams, while the Yanks and G-Men are "elite" teams with long storied histories.

[Senator Pardek]

.plus both the Mets and the Jets are perceived as "blue collar" teams

Good call - also, Jets/Mets Country extends to points east (LI) - while Yanks/Jints are in Westchester - No. NJ. It's hereditary, after all.

[sandalwood]

It seems to also follow the pattern of location:

Long Islanders/Queens= Mets, Jets, Islanders

NYC/north= Yankees, Giants, Rangers

Of course, I grew up on LI as a Jets/Mets/Rangers fan, but now I bleed Black and Gold!!!

Still prefer the Rangers whenever hockey comes back.