Well noobs will call you a hacker if you kill them and your high rank with big K/d, their arms or legs could be sticking out of wall trying to hide in corner, and you even saw them hide there, you kill them, and here is what usually happens:
The noob: Wow hacker killed me thru wall ** ** Mother **!
You: I don't hack noob, I'm high rank, you body was sticking out of wall, and I saw you run there, I'm not stupid...
The noob: NOOOOOOOOOOOOOOO, you are stupid cause you are a hack, and you are a nerd you stupid nerd, go your mom!!
People usually do not check you headshot percentage, usually they only look at your kdr rate. My advice to you would be to lower it to below 2. Lowering it too much and then getting a bunch of headshots would only make them more suspicous.