Because some of us have expensive breeds that would get stolen.Some prefer putting their cats on a lead rather then letting them out for fear they may get injured or killed.Others may not have a garden or the room to build a cat enclosure.
I would like my cat to have the best of both worlds and feel it’s a safer way.Our garden has no room for a massive enclosure as it’s full with furniture, a big pool, a shed and a trampoline.
If used from a kitten they can quickly adjust and love exploring. We take our British blue out on an extended lead in our garden and she absolutely loves it. I couldn’t care what others think I know my cat is very happy, healthy and loved.