Originally Posted by
jALIg
That is pretty common for many airlines. It is because they want to see that you fit the criteria before they assign the seat to you.
But that argument does not really count. E.g., Lufthansa allows you to OLCI select emergency row seats if you are an Elite traveller. If you have the audacity to show up with a broken leg or small kids, they will reseat you (probably happens 0.001% of all times since this benefit only applies to experienced Elite travellers).
I am mightily annoyed if airlines are too stupid to come up with common sensical solutions.