That would be good on a case by case basis, but I assume he wants this for all services. If he had like fifty pay walled sites that he never wanted coming up in searches, it would be cumbersome to have to add that in for any given search. You could store that on a notepad somewhere to copypasta but would still be a big pain.

One of the reasons I didn't go with another Android phone after my last one broke is I don't trust google. I noticed things like it recommending me add people I've been around on google plus. Recommending contacts based on some random text etc.