All the time! I'm not really sure why people look at it as a childs hobby, when in fact it is very difficult for a child to complete a model kit and make it look nice! In fact, most of the larger scale kits are way outside the realm of what a kid can pull off. Children typically (unless they have a parent who is into the hobby) don't have access to modeling tools outside an x-acto, some plastic cement, a few jars of testors paint, and a brush.
I look at scale modeling the same as I do painting, drawing, sculpting, etc. It's a craft and an art that takes years to hone to a science and a lifetime to truly master.
Currently Working On - DeAgostini Millennium Falcon, 1/16 MPC General Lee, Moebius Bride of Frankenstein
Next Up - Hobby Boss 1/350 USS Arizona, 1/24 Aoshima BTTF DeLorean, 1/25 Polar Lights BTTF part III DeLorean Mark IV