I'm going to go outside to do my business despite the fact I have a perfectly working toilet
Why are you going to the bathroom outside
I just feel like going outside
There are other people living in the local area and they may have to deal with the smell of your "business" if you do it outside. It's thoughtless of others when you relieve yourself outside like that.
Pfft, I don't care, I'm going to do it outside and it's not like anyone is smelling my shit
Even if someone doesn't smell it, it still makes the whole area feel worse. When you see dog poop on the sidewalk it's gross, so just imagine how much worse it would be to see human waste.