You also have to remember most people have put up a new antenna and likely tunes differently, requires extra tuning, etc so many are tuning an unknown antenna and maybe using a rig that is new to you also. For me worrying about someone tuning up near or on a freq I'm running is like getting your blood boiling about someone cutting you off in traffic. It's not worth the worry and there isn't anything you can do to change the other person. In the end being able to work and copy stations through the tuning is great training!
ARRL's objectives for FD, generally working as many stations as possible sounds somewhat like a contest.....
2. Object: To work as many stations as possible on any and all amateur bands (excluding the 60, 30, 17, and 12-meter bands) and in doing so to learn to operate in abnormal situations in less than optimal conditions. A premium is placed on developing skills to meet the challenges of emergency preparedness as well as to acquaint the general public with the capabilities of Amateur Radio.
Be sure to listen for my beacon on 28.278.8 MHz