According to zichron Yaakov (grandfather of Rabbi Lipschitz of the American Yated and secretary of the Agudah) they did not keep glatt in Lita because it was “motziin mamon shel yisrael shelo k’halacha”
Hmm. But they did keep other chumros which cost money.
Maybe it has to do with balancing the chomer of the chumrah, and the cost. So if the cost changes, it could change.
Aside 1: A friend of mine whose father owns a small shlachthois told me his father makes more money selling the treifos to goyim than selling the ksheiros to jews.
Aside 2: I have heard, that the adoption of glatt in america, was in response to mafia involvement in shechita, and their unwillingness to allow cows to be called “not kosher” since they lost money. So we started keeping glatt and saying the cow was just not glatt. Maybe an enterprising YWN-er can google around and find this.