4:2:2 is seldom if ever used for broadcast direct to homes - as it uses more bandwith than 4:2:0 which is the standard usually used (and also used by DVD, Bluray, HD-DVD, OTA Digital TV etc.) 4:2:0 has equal vertical and horizontal chroma resolution (ignoring some interlace issues), both are half that of the luminance resolution - whereas 4:2:2 has reduced horizontal chroma resolution, but vertical chroma resolution the same as the luma signal.
4:2:2 is used by broadcasters at higher datarates to backhaul live events from remote sites back to their broadcast centres, and also within studio and post-production environments, as it preserves a higher quality signal, which is important to ensure a high quality signal reaches us after a final 4:2:0 encode. Multiple 4:2:2 encode/decodes are friendlier to a video signal than concatenated 4:2:0 encode/decodes.
Broadcasters DO use 4:2:0 for some backhaul applications - such as news - where quality is less of an issue, and lower bandwith (i.e. lower cost) circuits are required.
Consumer STBs using consumer STB chipsets seldom include 4:2:2 capabilities as it is not a requirement in the consumer environment (as there is no consumer delivery system that uses it). It is useful for the enthusiast - and I suspect some low-end broadcasters would appreciate a cheap 4:2:2 receiver as well - but whilst most chipsets continue to be 4:2:0 in hardware this is a limitation that can't be easily worked around in a conventional receiver.
PCs and software based receivers that implement video decoding in software are able to decode 4:2:2 if they have the right codec support - which is why many enthusiasts also use a PC.