NursePhillips
In response to your question, "were you breaking the law", yes we were. In CT in those mid/late 1960s, sexual activity between unmarried people, was a violation of the state statue, a misdemeanor, "lascivious carriage". If ever arrested your name and address would appear in the area newspaper. The court disposition would be publicly reported. Have an arrest record for life. If one or both of the participants were married, the charge was elevated to a low felony, adultery. The way my girlfriend was often "dressed" in the car, she could, if they wanted be charged also with public nudity., because we are in a car in "public".
Now the police were very reluctant to ever arrest a couple "playing around" in a car, but they could if you pissed them off. If discovered in a motel, a bit more likely to result an arrest. They looked at "parking" on a lovers lane differently than what was considered a planned event in a hotel/motel. But motel discoveries were usually the result of an aggrieved spouse, or a drunken argument resulting in calling the police
At the time it was illegal to purchase condums from a pharmacy, unless you were married and had a doctor's prescription. The young high school guys that worked in the Pharmacies would often sell condums, if they could get them that they had stolen from the "secured" inventory in the halls of the high school. Every guy had one in his wallet, just in case of a sudden opportunity. Lack of available condums, the fear of the stigma of pregnancy led to the proliferation of talented young people in the art of performing oral sex.
As far as "Sister Superior", a teenage girl getting pregnant was about the most terrible event that could happen, to not only her, but her family. Abortion was illegal or done in the famous and very dangerous "back alley" clinic. Once revealed, have to immediately drop out of school until bady was delivered. The boy was expected to do the right thing and marry her. If the boy ran away from his responsibilities, the girl was often sent away to relatives during her pregnancy, so no one would really know. Being a "single mother" was not the badge of honor that it is considered today.
Play Boy magazine could only be sold from behind the counter in a brown paper bag. The laws didn't really change until the very late 1960s with the sexual revolution and the advent of the Pill. Social morality pressure and actual enforcement was much different in the decades prior, than what most folks on this site experienced coming of age .
The examples of possible "bad" thing happening, gave the offices the right and to a degree the responsibility to check parked cars. If someone died from carbon monoxide, the officer/s who had that beat would be called in and have to account for their time during that shift. They could BS their way out of it, but it would be an uncomfortable meeting, because your talking about dead bodies. There is no question, knowing men, there were possible visual benefit/s in checking out those parked cars in remote areas.
You probably fortunate to have never grown up and lived in that environment, but there were few illegitimate babies compared to the numbers today.