Well, for once, JF has got the edge on MOL.
But I can see a few practicalities to work out in addition to the excellent points already made above.
How are they going to levy this charge? Cash, cheque or card? What if the punter has spent their last euros, or whatever?
I can see some long queues at check-in, come Feb 1st, especially as some will be pre-charge, and presumably won't have to pay, and others won't.
Afaik, Flybe operate a 30 minute check-in. I've had a few close shaves in my time, but if a passenger turns up 35 minutes before his flight, only to find a big queue of people having to pay for their luggage, would any line manager dare to shut him out? Techinically, aren't pax supposed to have cleared check in by the closure time, rather than just be in the queue?