The sensors activate when the wheels start rotating at a certain mph. Then the signal is sent with the air pressure to the ecu. They cannot be put in the glove box. As for tpms being for idiots,... the gov mandated them.
The Firestone recall in the late 1990s (which was linked to more than 100 deaths from rollovers following tire tread-separation), pushed the United States Congress to legislate the TREAD Act. The Act mandated the use of a suitable TPMS technology in all light motor vehicles (under 10,000 pounds), to help alert drivers of under-inflation events. This act affects all light motor vehicles sold after September 1, 2007. Phase-in started in October 2005 at 20%, and reached 100% for models produced after September 2007. In the United States, as of 2008 all new passenger car models (M1) released must be equipped with a TPMS