I am currently on my study abroad so I have been living in a dorm and eating out of a mini fridge, so when I saw that there was REAL vegan food in Amsterdam I wasn't worried about the price. I would've gotten it if it was 25 euro a plate. But, the amount of food I got was a bit small for the 15 euros I paid.
Still, the food was AMAZING and the staff was extremely friendly. The man explained the menu to us very well and had provided us with great service. I reiterate, the food was incredible.
In my opinion, definitely worth the price, but yes, it is pretty expensive.