Are these guys club members? If so, make friends and let them enjoy learning. It sounds like they are beginners, and they will learn. Give them tips if they seem inclined to listen, and ask for consideration when you need to. If not, they both did a real jerkish thing and it would be appropriate to tell them about the club that pays for the field and regulates the flying. Perhaps they would like to join and learn the rules so that they can be welcome next time?