Maybe i'm missing something, or overlooking a ton of RL one handed catches, but arent even those numbers you both are quoting pretty high? I've seen 5 NFL games per week this season & the highlights of every game this season, and i think less than 1 one-handed catch per game is about right, and 90% of those are pretty basic, wide open catches where the QB throws it behind a guy and he manages to bring it in one-handed.
The one-handed catches in madden would probably be the play of the month in RL.