1 outdoor game a year to celebrate the heritage and just for kicks makes sense. 6 outdoor games 60 days is a shtick and kind of boring.
Outdoor games where the temp is >32F makes no sense.
You just knew after the very positive response to the first Buffalo-Pittsburgh game that they were going to squeeze the hell out of the concept. They stuck to 1 game per year for a brief time, but have gone nuts recently.