I think they are popular mainly within certain socio-economic/cultural circles. They started getting used more once a few celebrities started using them. I imagine they will rise some more, but I don't really expect them to get much more popular.
Don't get hung up on numbers. It could be that Hazel
don't even make the top 1000 in your area. They sure aren't used here. I can think of only one young Hazel
that I ever heard of. Her name is Alexis Hazel
, she's about ten, and Hazel
is after her grandmother or great-grandmother. She is not actually called Hazel