You are only thinking from the perspective of a self custody lightning wallet that can send and receive zaps. Most new users need a zap solution that is custodial but Alby is closed and WOS left town.

You don't need the extra step. But for people who only know and use custodial lightning solutions, it's pretty cool and simple. I can appreciate the privacy add, too. I like the idea of a cheap "tumbler" between my purchase from Robosats and my node.