@kkarhan @paulasadoorian
Its gotten better now that they've been mandatory for a while and there's been some standardization, but there was a while where fitting a TPMS sensor to a fair portion of aftermarket wheels either wasn't possible or would require a big, ugly, stack of weights to balance out (no go for a lot of people).
Lots of those cars and wheels are still out there.
@kkarhan @paulasadoorian Oh, no, no, no; there are wheel and sensor combinations where the sensors physically will not fit the wheels.
On others, the sensor will fit but the wheels weren't designed with the sensor weight in mind so you'd have to stack weights three or four layers high on the other side to balance... which is ugly... which people who are buying ridiculously expensive wheels for looks don't want.
Source: I worked at a tire shop during the time TPMS systems were becoming standard.