Hey, man, I'm not trying to refute your statement. No need to get defensive, and everything...
But if the time and place was right, yes, Batman would see the glare off the scope lens. Lets say they're in the middle of the desert, where the sun is shining bright, and there is NOTHING that could cast a flashy reflection...
Hell, nobody specified the location of this showdown, so I took a page out of Indiana Jones and the Last Crusade when they see the glare off of his binocs when he's in the hills.
Personally, I think this is a stupid argument...
Batman and Punisher have no reason to fight, except when they cross paths in the wrong circumstances. There's no reason why the Punisher would be hunting Batman, so he couldn't get a surprise attack.
What I mean is they're both after the same crook, and find him at the same time. Punisher wants a frag, but Batman wants to leave him to the cops. Such tensions raise tempers, and it's not long before they're at eachother's throats. In which case, Batman, the obvious superior, would lay the obvious smack down.