If all you want is "just to ride around", you can do it for free anywhere that has a road. You're thinking of the track completely in the wrong way so that's why it seems expensive to you.
How long (how many miles) have you ridden? Is this your first bike? Have you added in the costs of bike equipment and riding gear? Fuel, tires, brake pads, tools, etc. etc. will cost you substantially more than the entrance fee.