They want to monetise EVERY aspect of your life - "For your convenience" but never forget that they see YOU as the product to be sold. If they can analyse your poop, they can work out if you are eating meat or dairy, what chemicals or drugs are in your system and all sorts of medical information about you. There may be legitimate uses for this information but never forget that it could be subpoenaed or used in ways we haven't even thought about yet!