Yeah I had one and the battery life was not great, so you could not use it in all of those places unless you were rich and had an endless supply of AA batteries. I had the original B&W Gameboy and the added magnifier / light combo that took even more batteries.

It was good for a couple hours on one set of 4 AA batteries if I recall correctly. We did have rechargables back then but they were Ni-Cad and they sucked, took forever to recharge.