They're both as inherently pointless as each other.
Or maybe here's a crazy min of logic, that you seem unable to ever comprehend, TEA. Maybe different things have a different sense of value to different people, instead of whatever value *you* prescribe to them being the only valid one.
Myself, I think achievements and trophies are fun, but they'll never define myself gameplay experience. I have absolutely no desire to play a game a special way just to get a trophy or achievememt.
I'll get the 100% prize bubbles trophy in LittleBigPlanet because I want to get the prize bubbles, not because I want to get the trophy. On the same token, I finished Bayonetta on Infinite Climax mode not so I could get all the achievements, but because I thought the game was worth the thorough completion.
But how, here's a crazy form of thinking that may go over your head, my little wannabe gangsta buddy.... people have different tastes.
I don't personally have any interest in getting a big number on my GamerScore or reaching a high score on my PSN account, but hey, if someone else does, fair dues to them. It's all just for fun.