i think they love us because they get a crapload of views from pony-related videos, and more views might get them more income. Just like Hasbro made massive profits in the TV ratings, perhaps the bronies have given youtube significant profits in the viewing stakes? Just a theory.
It's not old for those who don't have a reason to type a ponies name on it's own that often. Most of my youtube watching is done through my subscriber module. And even if i look for new stuff, it's under the broader term of MLP.