I wanted to clarify that, although "the chair doesn't lead to the table" for me, I love the chair not only as a separate revenue stream as mentioned above, but also for use all by itself in the office for some clients. For a couple years, I had a weekly 90-minute chair client -- she paid my rent all by herself. And I have others, less regular, but the chair is the only thing that has convinced them to have bodywork.
Owning a chair also enables you to do festival/farmers' market type work when you want to, which can be lucrative and rewarding by itself too. Basically for me it's hard to imagine being without the flexibility a chair affords my practice. It has paid for itself several times over the last 4 years.