I've been an F&I Manager for 20 years. I don't even have to read that (but I will). There are enough sharks out there that I wouldn't EVER tell anyone to let their guard down in the finance office.
Everyone is different. How another person conducts themselves behind the desk, that is out of my control. All I can do is conduct myself professionally. I try to conduct my business in a way that wouldn't embarrass my family, if they were sitting in on the delivery, and I think I make a pretty good living at it. Remember that what is represented here on this forum is far from a cross-section of the car buying population. F&I products are not for everyone, nor should they be. However, there are people whom they benefit. My job, as I see it, is finding those people and offering them those products.
I'm lucky; it's not all that hard a job, I get to sit in a nice air conditioned office, and I get paid to do it. I don't have to wear a neck tie. The downside is that I put in a lot of hours. But, I like people, nd I like talkming to them, so it's a pretty good match I guess. It beats doing a lot of other things. Or not working at all.
One thing: State laws very. what MILOIOWA says is true in some states, not true in others. In many states the price of F&I products is capped; in some states, it is actually fixed and mandated (service contracts in Florida). One thing that he says that is absolutely true, do your research. Knowledge is power, and the more you know, the more you can make the decision that is right for you.