Of course that's true with lots of things. Cameras, audio equipment, video gear. Whenever I go into B&H Photo in NYC I'm always struck by how quickly the prices go up as you transition from pretty serviceable amateur gear to the pro stuff.
On the other hand, the farther you get up into production trades the more money is riding not just on your performance but on the performance of the people that are relying on you.
If I'm making a short film with my buddies for fun and I get a technical problem that prevents to director from monitoring the shot on a screen, oh well... if there are 30 people in the production and everyone is held up for 5min, that gets really expensive fast.
Better/faster autofocus (usually), fully weather-sealed body (!), larger sensor (depending on what you need), dual-native ISO, etc etc
Plus other features that are technically still convenience, but can matter a great deal to a pro.
- Example1: Panasonic G85 has a couple reconfigurable buttons, but on the GH5 nearly every physical button can be configured to whatever setting you want.
- Example2: Dual memory-card slots for instant backups (some prosumer cameras only have 1 slot)
However, I agree that many salespeople will try to sell pro gear to a hobbyist when they really don't need it.
And high end audio - turntables for $650k, etc.
But honestly I'm being cynical for no reason here. Those guy can spend money on whatever makes them happy. I am in no place to judge.