Priority Boarding on Ryanair - You don't have to pay!

Lots of discussion on this one but it's all part of the game. Ryanair offer tickets for as little as 1p (and yes they are real - I just picked a route and two dates at random and they were both 1p flights), and then try and take enough money to make a profit out of you by other means. The latest trick is to charge you for priorty boarding automatically if you choose not to pay to check a bag.

Your mission is to not pay for as many extras as possible. You can escape this charge, but it certainly isn't obvious how. Let's look at the booking screen:

Your only options are to choose one or more bags, and pay for them, or choose no bags and pay for priority boarding. Oh dear.