Coworking spaces aren't about work. As a small business owner who uses a coworking space, my perspective is that it's about signaling that you are a real business with a business address. Working from home may work for freelancers or online only businesses, but the second you start signing contracts or having meetings, you need a professional space to be taken seriously.
That said, it's incredibly hard for me to get anything done in a noisy environment with no visual barriers and so many wantrepreneurs around. I like the coffee, camaraderie and event spaces, but for most days, working from home is sufficient.