Your guest bringing the bottles may have felt that separate wine glasses were needed, and so asking him to cope without while he was being so generous does seem a bit ungrateful. I could imagine myself bringing a fine old red wine out to share with friends and then being told that I was not going to be allowed to decant it.

As others have mentioned, I'd have been more inclined to explain the situation to the restaurant and insist on offering them what they feel proportionate compensation for the extra glasses.