The taste of cum is not exactly like whipped cream on ice cream - so I don't blame anybody for not taking cum in their mouths.. BUT in gay porn, I find it very annoying that they almost never get the cum IN their mouths. The cum winds up on their chests, face, nose, eyes, etc. They could easily show it go IN the mouth, and then turn the camera away to spit it out. I don't like to SEE it spit out either. It's nice to imagine it being swallowed.
I know that in straight porn, the women suck down cum like it is candy. They have to, because there is so much straight porn that they can't hold back and expect to sell their porn.
It always annoys me too. The funny thing is that they have their mouths open as if they are ready to swallow, but "somehow" the cum just ends up everywhere but inside the mouth. There are those that do us a "favor" by licking the head once the cumshot is over.
I even saw a few videos where the top asks the bottom "do you want to swallow my load" (or something like that) to which the bottom responds: "yes" but even then, no swallowing!