There are certain peeps that have that ability as I have unfortuntely run into them. Not sure how they get that much power, but it happens.

by inserting a "robots.txt" file into the root directory of your site.

I just embed text in a picture. It is even easier to do a screen capture of a document, then convert it to a picture. When placed back into a document or web site it can be seamless and the bots are unable to harvest text from a picture.  PM me for more info.  See my example here.