Different legal environment. Until 1908, player piano companies didn't have to pay royalties to composers. See White-Smith Music Publishing Co. v. Apollo Co..[1] So, in its growth period, the player piano industry didn't need to acquire music rights.
Then Congress changed the law, to create the "mechanical license" right to play out the song from a storage device.
[1] https://en.wikipedia.org/wiki/White-Smith_Music_Publishing_C....