I bought a thin gaming laptop last year (in my case a razer blade, but there are several similar laptops from other manufacturers available now) and honestly it's one of the best development laptops I've had (compared to the Thinkpads and MBPs I've had from work). Plenty of CPU and memory, and a nice screen, and I find that the keyboards on gaming laptops are more comfortable than a lot of other laptops these days).
Agreed. For my use I don't need particularly light laptop, or long battery life so I choose gaming laptops too. Simply, because they are packed with the most powerful hardware.