This was just my opinion, and it was not based on logic: I battled through and now I'm a happy trailing comma-er. But if I think about your question, I'd say th

This was just my opinion, and it was not based on logic: I battled through and now I'm a happy trailing comma-er. But if I think about your question, I'd say the answer was because commas are the only part of coding that has a strong resemblance to written english in that you commonly use them to separate items a list.