If you're into just geeking out on railroad jargon, I suppose a scanner might not be a horrible purchase. If you're looking into getting a scanner to make your first train hopping experience a little easier, it's probably going to let you down. It's basically gonna be a bunch of hotbox/defect detectors, high wide detectors and a lot of railroad jargon, releasing track authority and repeating each other. I bet it would take months of listening to scanners to hear something that's actually of use to a rider.
Then you'd have to figure out all the different frequencies, and sometimes there's silence so it's hard to scan for them. I'm not trying to talk you out of buying one, but it might be a good idea to try and find some conversations between dispatchers and train crews on YouTube. Have a listen to those, and decide if you think it was helpful enough to spend upwards of $75.00 on.