I think the difference here is that there is no association of the search term with a specific search. If they see a term, they simply add 1 to the counter. Of course, that is probably vastly simplifying it. Basically, your search is thrown into a pool with all of the other searches. It possibly never even has an id associated with it. Just a frequency number.
For example, say I start to type "movie t", it'll see that often times after the word "movie", "times" appears at a high frequency so that could be one of the suggestions. I don't see how this introduces a privacy issue unless they are saving the searches by some personal identification number (whether thats an ip, user id, computer, etc), which they specifically deny. Without the specific identifier, there is no way to say it was user A who searched for "movie times" 300 times in a row and not 300 different users searching for "movie times"
For example, say I start to type "movie t", it'll see that often times after the word "movie", "times" appears at a high frequency so that could be one of the suggestions. I don't see how this introduces a privacy issue unless they are saving the searches by some personal identification number (whether thats an ip, user id, computer, etc), which they specifically deny. Without the specific identifier, there is no way to say it was user A who searched for "movie times" 300 times in a row and not 300 different users searching for "movie times"