The Trainline charges you a premium because it is a private company selling extra services. You chose to use it because, I presume, you like their UI or help function or mobile ticketing or something else which is of value to you. Of course, you can also choose to use one of a dozen different apps which charge you no extra fee. Or you can use the machines at the station. Or - and this is the key part - you can talk to a person at the station. You'll notice in my post I didn't propose getting rid of people. They just don't need to be trapped behind a glass screen all day.