I'm a thank you note sender as a general matter. But recently, H & I threw a party, and instead of bringing a bottle of wine or a six-pack of beer or a dessert, a few people brought us actual gifts for us (one took a cutting of her own geranium for us and put it, potted, in really pretty little birdcage, for example).
I'm torn... I was about to send thank you notes to those who gave us gifts for us, as opposed to consumables for the party, but then on second thought it seemed kind of like overkill... like the gifts were a thank you from them to us for inviting & hosting them, and so thanking them for a thank you would be silly.
You only live once, but if you do it right, once is enough. ~Mae West