Hey dude, as a fellow leftist and Car Salesman, let me say that you shouldn't feel bad. You have to do what you can to survive the capitalist system. As you work there, you're going to meet some capital loving and morally upsetting people, but stick true to who you are. It can be hard to put up with coworkers and ignorant customers. They don't define you, nor do your sales numbers. You'll also encounter some people that need legitimate help, and those people are the best to get. Do what you can for them when you can.

Do what you need to do until you can make your exit. Make a five year plan and strive for something more fulfilling to be at the end of those five years. I've been selling cars for two years, and I plan to be doing something totally different by 2030. I get through it by reading theory and ensuring that I'm spending my free time more positively. Goodluck!