I think it’s meaningless as well, but I can also see why people don’t like it.
It takes an unmitigated amount of gall to take it on yourself to do something like that, that you believe is real, for (or to) someone you don’t know without their or their relatives knowledge or consent.
It doesn’t affect me in any way. I don’t believe it is real therefore it holds no power in my mind. I can see the rationale for it but it is 100% worldly. I can see the new Emergent Church doing it because it would appeal to the spiritually weak who would be more at ease if their dead relatives got a chance to escape Hell. I know people who resist their own Salvation because they don’t want to deal with daddy dying unSaved. “Shoot fire, we’ll just wish daddy into Heaven then”.
I’m not saying Mormons are weak but that weak people may be drawn to the practice.