Actually we can use this analogy. Who lives longer? a skinny man or a fat man? Naturally we'd assume the thinner man cos hes less prone to sickness or diseases or what not, but we can also assume the fat man, since he is eating healthily.
Either way, both are men, and die at some point.
Though the assumption is hard, strings are similar. Thicker strings just means more mass, it may or may not affect life. Observe your strings I guess. The more frequent you notice your acoustic strings last longer, the more probable that they actually do last longer.