No, it is completely unethical. Using any form of improper or immoral behavior to obtain a discount is unacceptable in society. Business transactions should be based on fairness, legality, and integrity.
Sharing such stories is not appropriate as it involves very private and often inappropriate sexual content. Such topics should be kept within the boundaries of a consensual and private relationship.
Probably not. It sounds like a rather strange and made - up combination of words. There's no evidence to suggest it's a real story that has any sort of widespread or significant meaning.
Since I don't have any information regarding this particular 'big mac car blowjob story', it could be a random combination of words that someone has created for an unknown purpose, perhaps for a creative writing exercise in a very small group or just a very odd joke among friends.
I don't recommend seeking such inappropriate and unethical content. It's important to focus on positive and respectful forms of learning and interaction.
No, not all sex in the car stories are fictional. Some might be based on real - life experiences that people choose to share, though these are often private and not very common to be openly discussed in a proper social context.
Car sex is generally considered inappropriate in public places due to the lack of privacy. One taboo is doing it in a parked car in a public parking lot where people can easily see. Another is having car sex while driving which is extremely dangerous and illegal as it can cause distractions and lead to accidents.