In our prehistoric past, we would have lived in extended families, surrounded by kin whose interests we might have wanted to promote because they shared our genes. Now we live in big cities. We are not among kin nor people who will ever reciprocate our good deeds. It doesn't matter. Just as people engaged in sex with contraception are not aware of being motivated by a drive to have babies, it doesn't cross our mind that the reason for do-gooding is based in the fact that our primitive ancestors lived in small groups.
Things exist either because they have recently come into existence or because they have qualities that made them unlikely to be destroyed in the past.
The recurrent laryngeal nerve - which runs from the head to the voice box - goes all the way down into the chest, loops around a major artery, then goes all the way back up again. It goes right past the larynx on the way down. All a decent designer would have to do is loop it off at that point. What we're looking at is the legacy of history.