One of the features added to Second Life some time ago is projectors, lights that shine on things. Bryn Oh used a headlamp thing for use by those visiting his latest exhibit, which is a projector. But, we see little use of projectors as lights in SL. Or maybe we just don’t notice them.
There is the problem of many people probably not having Sun/Moon + Projectors enabled in their graphics preferences for performance reasons. That is a problem for those building places. They want the majority of visitors to see their creation as built. So, they often skip using Projectors for lighting. But, for photography performance is generally not a primary issue and what the camera sees is up to the photographer. Everyone will see the photograph as captured as in general everyone’s computer settings are similar. So, there is no reason not to use Sun/Moon + Projectors. We just want to light our scene to create the image we want.
In RL photography lighting is a big part of it. For portrait photography it is somewhere between a science and an art. Lighting is used in capturing most all commercial images too.