I am surprised that the bolts for the windshield wipers are not protected with black a plastic cover for example.

Any recommendations?

 

I think I remember this coming up a while back, and I don't remember anyone saying theirs had covers.

Having said that, the bolts are completely covered when the hood is closed, so they're no different than any other bolt in the engine bay as far as exposure is concerned. I've driven my '07 V8V through rain, snow, and even ice storms, with nearly 60k miles on it now, and those bolts still look fine on my car. From my experience, and from others have said, I don't think they actually need covers.