I wud agree wid ur first friend ... " we all need sex " sex remains sex but wen u connect emotionally, it becomes makin love .. which is another blasted concept introduced by romantics like u. I am answerin ur questions in d order in which they were asked.
a) privacy :- religion ( and their various pimps ) over the period of time conditioned people to believe sex is a bad thing to do, the original sin. So over d years, ppl feel guilty abd wud rather not do it in public.
b) Lookin face to face isjust a lack of knowledge of positions .... or mebbe ppl r nervous abt it n follow d tried, easier n tested method of the missionary position. Lookin in the eyes or not is not a necesssity while making out. It does make the experience a lil better though.
c) We wud continue having sex all the continue if possible. Man / woman are not merely social animals ... they are sexual creatures as well.
d) We dont have a mating season cause we are not "stupid" animals. We are higher species and are capable to make our own choices. the instirument / organ which we use to do this is caled brains ( incase you have never heard about it )
