Erroneous assumption. It relies on the idea that the present paradigm has provided for all the possible options, which it hasn't.
Of course a person could be in business and want to preclude others for lots of different reasons. No shirt, no shoes, no money, not old enough, wrong sex, carrying a gerbil in their pocket, etc.
The left alone part when I used it, wasn't meant they necessarily want to be left alone by the people they chose to interact with, it means left alone by an unwanted and uninvolved third party (the nanny state). You can't deny the nanny state doesn't intervene can you?