You can say sex when you mean sex and f*ck when you mean f*ck. Yes they are just words and I really like to use them in many different situations. I think there is nothing more annoying than a prude who expects people around them to say "oh poo" when they get riled up in the face of a threat of grave offense. To me saying "Jesus Christ" has the mentioned 7 affects, but if I said it around a Christian they would recoil in horror and insist that I "check myself". The people I surround myself with are from all over the world and from different backgrounds since I love surrounding myself with colourful speech. A "bad word" to one, may be a fun word to others. One should never impose oneself on people and I assure you that telling people how to speak, just because it makes you feel bad about pooing when you think of the word shit, is madness and rather invasive from a social stand point. We live in a diverse world so be prepared to get comfortable outside of your comfort zones ;)