These 'punters' are certainly not 'hapless' if they have agreed to all the conditions on the website.
And can I purchase a flight without agreeing to all the conditions? No! So therefore I have no more "agreed" to the conditions than a bank clerk "agrees" to hand money to an armed robber.
(For the avoidance of doubt, I'm not saying Ryanair rob their customers, I'm just saying duress is not agreement).