A midwestern railfan club I belong to has sponsored several UP trips over the years. One thing we've done is to alert the local law enforcement agencies of the trip to keep an eye on the crazies and also to block roads when there are photo run buys.
We've also been known to take cell phones along and turn in drivers who drive erratically in chasing the trips.
One nice thing about chasing C&TS trips is the train goes slow enough where numerous shots are possible. I'm not sure I'd want to enter the Steam Excursion 500 anymore for main line trips.
Funny thing is during the early 1990's, UP ferry moves across Nebraska had become so common place that often 4 or 5 of us would out there and that was it.