This is a team that had a Cat-urday promotion for crying out loud. And a Star Wars Day. And people think this is dumb? There are Nats fans who are fans purely because of their tie to the Expos. On this board. They may not be you, but one game out of 82 seems like a small sacrifice.
I don't care about Frank Howard and Walter Johnson. And I am sure I am not the only one. They have less tie to this franchise than the Expos, honestly.
People were asked what they think. People replied, many of whom had generations of baseball taken away from the nation's capital largely because of clown show MLB executive policies and are more than a little tired of machinations from same. Wanting to prioritize a long history going forward in the area where it happened is more than reasonable.
I'll go back to the Ravens and Cleveland example. Cleveland prioritized keeping the history in the city where the fans were who felt a special affinity. In like manner, Baltimore focuses on its own history despite the current franchise itself being elsewhere pre-mid 1990s.
I know the Expos post-move have had events at the Bell Centre, and the locals there are able to appreciate it. I stood and clapped respectfully for 5-10 minute commemoration events at Nats Park related to Andre Dawson and Gary Carter, but I think historical events make much more sense and carry much more meaning and significance in the area where the people played their home game.
Even a spring training game where the Québécois snow birds could see pros sporting the unis makes more sense than a full Expos day in DC. They could do it so that people from Montreal also could see that on TV just as readily as they could a regular season game. (If one of my teams moved, I'd likely be more irked by it than anything.)