Does it look bad not to do it? If so, why is it optional?
I don’t know, but I will tell you what I assume? I assume that they do not want to discriminate against students whose parents are not able to write or not comfortable with writing.
IMHO, though, I would always include a statement (even if dictated or translated) because one thing I do think they may find important is to know that your parents support your application. I personally would not want to leave the impression that the parents are not in agreement about applying to the BS.
When they say it’s optional it means that the parents that actually do it seem to care about their child getting in and the parents that don’t seem to not care at all. So I would highly recommend doing it because it really matters.
Thanks. Good points.