Are dark-skinned people just as prone to skin cancer as fair-skinned people?

I have naturally dark skin. A spend a lot of time outdoors in the summer and when I do that, I wear sunscreen-usually a 15 but if I'm the mountains I wear a 30. Now it is winter and occasionally I go to the tanning booth because it's so relaxing and puts me in an escapist summery state of mind. But I'm not an addict like some people. I don't want to get skin cancer, but why should I avoid the sun? Why should I stay indoors all summer? Shouldn't people just be patching up the ozone instead? It's not fair.