Do you need to rinse vegetables that can be peeled?
While I don't always practice what I preach, in the interest of food safety, I would recommend rinsing any vegetable or fruits before peeling. 

The reason for this is that when you cut into an unwashed vegetable or fruit, any contaminants on the outer surface are transferred to the part of the item you are going to eat.

While it doesn't happen often, some foods have been contaminated by E. coli, salmonella, pesticides, fertilizer residue, etc., when not rinsed first. In the worst cases people have become ill from it.

Garlic may be the exception as the outer peel is usually removed by hand before doing anything to the individual cloves. (Except when roasting and the top is cut off.) Onions could also be an exception if you are able to remove all of the outer peeling so that your knife will not go through it when cutting the onion.