I completely understand your concern that if you do test postive at 36 weeks and your midwife is able to let you decline antibiotics in labor (some standards are that if you decide to test, you are bound to follow the result)that if you do transport all kinds of stuff will be done to the baby.
This is unfortunately true. GBS CAN be a serious concern for some babies - the problem is of course, no one knows which ones. This is a real tough decision (again, welcome to being a parent!)and I would NEVER say make a decision out of fear, but oh, my I've seen some really terrible interventions done to newborns because their GBS "status" was positive or even UNKNOWN.
What does your midwife say?
My own personal decision here is to have the antibiotics if I test positive. I'll find out next visit, I'm 38 weeks. But I know my situation is that usually there isn't time
for much to get to the baby!
Good luck! and best wishes for a lovely, peaceful, natural birth.