It's incredibly common in work environments, especially if you're working with customers. I work in sales and see and use it every day. I'm not sure where everyone learns keigo, but I do know these days young people aren't always as good at keigo as they should be before they get in the workplace. I've even had jokes that mine is better than some of my co-workers. There's a sort of "lazy" form of keigo (it's just the potential form used as keigo) that's used somewhat regularly but it's not the most proper. I think you can start working on keigo once you've got all the basic grammar down. As long as you're using the desu/masu form, you're probably not going to incredibly offend anyone (they'll let is slide since you're not a native speaker) but if you can use keigo properly you'll really impress a lot of people.

I think my comment for other question confused you, I agree with Jordan's opinion. We have a lot of ways of saying depending on the person whom we talk with. Japanese people learn how to use them when we are growing up and they are very dificult for us. However, you don't worry about them now, please learn the normal forms of formal and informal first.