Your reasoning is poor. The point of taking a course isn't to get an A. No, but sometimes an A makes the difference between graduating or not. It's not like

Your reasoning is poor. The point of taking a course isn't to get an A. No, but sometimes an A makes the difference between graduating or not. It's not like the course held a gun to their head and made them cheat. No, but if cheating in the class is common, then it's likely that the difficulty of the class material is artificially inflated to account for students' artificially high performance. If you know this, the professor doesn't know this, and you need an A, then it may be that the only way to get an A is to cheat.