When I travel around the world, I can use my home office based computers by using a notebook computer and modem. While I may be sitting in a hotel, on an airplane, or in a client's office, work is being done electronically in my home office. Faxes, messages, and information are all routed to me in my home office and can be available to me anywhere in the world at the push of a button. I don't need to be IN my office, but I do need the office. I work in my office electronically.
Home based businesses are mostly cashflow based businesses.
We don't have a ready equities market, there is little in the way of business loans, and lines of credit are generally not available to us. We run our businesses based on short term positive cashflow and controlling costs. Having our offices in our homes is one way of controlling overhead. Big business turns to home based businesses for outsourcing. We reduce costs and can often do a better job.