Ryanair don't do that. The price they advertise at the flight choice time is the price you pay. THey then try shove extras down your throat, but you're not obligated to buy travel insurance, rent a car, use their jet ski etc .
In my experience, EasyJet do offer you lots of low value "extras", but they do not try to trick you into taking them in the same way as RyanAir do (did?).
So I stand by my example, although perhaps it's not the best one available :-)