Tom, do you agree there is a difference between washin, rinsing, and scrubbing. When it comes to grapes (something I know nothing about), seems like you wouldn't want to "wash" to agressively.
Personally, if you get them, (any fruit/produce) from the grocery store I think it would be silly NOT to at least rinse them off. Commercially grown fruit, or produce for that matter, will almost certainly been sprayed with some sort of an insectiside, or who knows what else.
I remeber reading once, (long before getting hooked on making wine), that commercially grown strawberries were one of the very worst to have chemicals sprayed on them.
I would think naturally grown fruits/berries have a little more chance of being free from these concerns.
Any thoughts?
Troy