The problem with working at home is not that you never leave home. The problem is that you never leave the office. Work will consume you, and take over your life. Take it from someone who knows.
Thanks so much for the comment Paul, this isn't something I have experienced yet but I had a feeling that it might be an issue so I have already researched co-working spaces I could invest in should this become an issue.
I've never really suffered from any of these problems. Every day I set myself up for 7.5 hours of work, and 2 hours of breaks/checking email in the morning/lunch. After those 9.5 hours are up, I'm free to do what I want. At a bare minimum I do 37.5 hours a week.