RFID in Lawncare

So trivially simple - lawnmowers already hog a tonne of power - why not a few more milliWatts to be tag-aware - when you don't want them chopping off sprinkler heads and dissecting drip-irrigation guts, just stick a tag that you can get from HD or Lowes. Jeez. Why must we wait for the Japs and Israelis to invent everything?