I do whenever I have some money to spare. I consider it as a cheap investment with a high return in the end. Also, I'm not a paranoid to check out prices too often in a single day, so buying and forgetting is a nice way to do when you invest in bitcoins.
One of my problems is that. It is like a disease and I always look into its price if there is a big change even if I really dont have that big investment. I think those who should always look into its price are those putting a lot of money in bitcoin.
the same for me i think that it is just like an addiction for me to be honest though i still buying a lot of bitcoins right now to make profit