Market forces - if people pay, then it aint overpriced, sorry. If it's too expensive for you, do something cheaper. buying a smaller boat is always an option.
I'm always interested in the concept of "ordinary people". These are so very rarely the same kind of people as the people using the term... and the authority is not human. It's a charitable business, not a person. Plus, publishing the costs of stuff isn't particularly sneaky.
Not needing something you love doing is a bit odd too - usually, we want to do stuff we love doing rather than walk away because someone is asking for money to pay for it. But it all comes down to what you want to spend your money on - me, I'll keep the boat on the water for as long as I can, which may not be much longer anyway, but I don't give a toss about CRT, or the legality of charging me mooring fees, or whether CRT can charge me to moor for a couple of days somewhere. Sitting in the middle of nowhere, miles from traffic, towns and people, perched on the back of the tub reading a book in the sun listening to the birds sing is worth a couple of grand a year. You won't find that anywhere else in this country without having to climb a mountain.