Earlier quoted context omitted.
So when I google 'suicide' it's OK for Google to know whether I'm clicking on the Samaritans or the Wikipedia article? And when I Google 'rape' it's OK for Google to know whether I click on a news article about a string of recent rapes or click through to rape fetish erotica website? Not everything is black or white.
To your first question: YES, it's 100% okay for them to receive this query (a distinct issue from 'Google knowing'). I think in this case it's pretty black or white, because people would ordinarily take the time to add to their search queries. If people want to see results on (whatever fetish), do you think they would just Google the word 'sex' and then go from there, under cover that they might have just been lookin…
...and then being able to get you fired, steal your identity, or otherwise affect your life without your knowledge because you happen to enjoy a certain kind of food your boss doesn't like.