This is all speculation at this point, but it could also explain the absence of the Ant-Man and Hawkeye in the Infinity War promotional campaign.
For now, we’ll just have to wait and see how the battle with Thanos pans out, but Ant-Man and Hawkeye will be involved in the story in some way or another after feeling particularly burned from the events of Captain America: Civil War. Hawkeye and Ant-Man may play a larger part in Infinity War than anybody can imagine right now along with Doctor Strange.
Are all 22 of the Marvel superheroes we’ve seen on recent Avengers: Infinity War characters posters about to meet their fate?
The same can be said about Paul Rudd’s Ant-Man, since he hasn’t been featured in any of the promotional material for Infinity War either.