Actually, it’s easy to understand.
Such people feel that they ‘own’ their faith, and that they can determine what exactly they ‘take’ or ‘get’ from it.
Sometimes it’s cultural. They want all the warm fuzzies of whatever their cultural Catholicism is noted for. . .but none of the bother of the actual practice of the religion. These are the ones who wear rosaries or jeweled crucifixes, make a big point of dressing in green on St. Patrick’s Day, buy gifts on Christmas, eat ham on Easter, and ‘use’ Catholicism to make themselves look good.
If they’re politicians, so much the better. They can attempt to play both sides. . .appeal to any of their constituents (hey, we’re both Catholics, ya know? ) whether the constituents are faithful (hey, we’re BOTH Catholics, ya know?) or not so faithful, (hey, we’re both Catholics, but you and I know the REAL deal and we’re working for the REAL ‘Christ’, ya know?). And they really, REALLY get brownie points from the virulently antiCatholic if they PRESENT ourselves as Catholic yet pointedly diverge from the teaching.
And of course, the issue of pride. Pride in determining that THEY (they alone) are the ‘right’ kind of Catholic, that they (they alone) have the truth. If the bishop or others DARE to ‘defy’ them, well, that just shows how wonderful Mr. Kennedy and his ilk are (in their minds) because they aren’t going to give those bishops the satisfaction of ‘getting rid of them’. Oh, no, Mr. Kennedy is bound and determined that if HE wants to claim Catholicism, he ‘damn well’ will, and to hell with anybody who says otherwise. It is a total power trip and has nothing to do with Christ (whom few of these people would even recognize, sadly). It’s all “my wants, my needs, my thoughts, my decisions, my life, me me me.”