After reading multiple interview memoirs, I get the impression that the agencies are risk-averse to the point of paranoia. The analogy I could come up with is that if you report that you have a minor paper cut, they think you have sepsis and tetanus.

For real, 

"You have a spicy sex life? So did Robert Hanssen, you are a spy!"

"You mentioned whistleblowing (nevermind that you were feeling bummed for the day and that it was just an off-hand remark)? You must be the next Snowden, you are fired!"

"You got laid with a teen in high school (nevermind that you were a teen back then and that your partner was the same grade as you)? You came in sexual contact with a minor!"

"You smoked that Mary Jane a couple times in that one frat party? You are a habitual drug user!"

I am quite sure that plenty more examples exist in terms of blowing things out of proportion. Anyone care to share some more  ?