Wonder if I can buy adspace in people's personal outhouses.

MORE U.S. HOMES HAVE OUTHOUSES THAN TIVOS Outhouses vs. TiVos
A case of the law of large numbers coming into play? Hardly. In a neighborhood of 200 homes, only one on average has a TiVo. More U.S. homes have outhouses (671,000) than TiVos (504,000 to 514,000).