If you like to do bird photography, then you're probably very well aware of how much your back can hurt you after walking around for a while. If you're not the type to sit in your car and photograph but instead actively go hiking, then you've come to the right place.
The act of focus stacking is one of the most important and best ways to get the sharpest macro photos. While photographers, for years, would just stop the lens down and use off-camera lighting, that's not always necessary now.
For some photographers, it's full-frame or nothing. And those photographers will probably never be convinced otherwise. The best non full frame cameras, however, are capable of doing some very incredible things that full frame cameras can't.
One of the most liberating things about modern cameras is just how far the technology has come in some of them. Lots of photographers love to shoot astrophotography, but then end up spending a while in post-production layering photos and compositing things.