Chris,
Saw your post and stirred my curiosity.
I'm not sure what the scoop is on exchange rates and perhaps others will know more. I know that Jet2 let me pay with debit cards for free whilst Ryanair require me to have either a Mastercard Cash Passport or guess what a pre-paid Ryanair Card.
Ryanair gets such bad press but Jet2 are driving pax away with their greed.
Let's compare....
It is bad enough having to pay ridiculously expensive fees for baggage, negotiate around the hard sell for allocated seats (which I reckon 70% of pax fall for), then the extortionate credit card fees
Jet2 booking fee NIL
Ryanair Booking Fee - £6
Jet2 Airport Check In - NIL
Ryanair Airport Check In - £60
Jet2 Booked Seat - £5.99
Ryainair Reserved Seating - £10.00
Jet2 Sports Equipment - £25
Ryanair Sports Equipment - £50
Jet2 2 Bags Fee - £32.98
Ryanair 2 Bags Fee - £50 - £90
It seems like you've maybe had a bad day but when I booked with Jet2 I simply clicked "Continue" to avoid any seat charges and they are considerably cheaper than Ryanair (your example I have not beef either way). All airlines try to upsell. I just booked a trip with BA who try to sell me hotels, insurance, booked seat costs etc too, so nothing new there.
Not sure why you picked up on Jet2 being "greedy" but doesn't really stack up compared to the the rest of the carriers.