They're not a big hit group. Big hit buy their company that's not the same thing at all.
By the time mago came about gfriend were an institution. SM did not save RBB, zim or UU. Sometimes a song fans like just does not work with non fans.
That gfriend had nothing nice to say about BH and lots of nice about source at disbandment paints a clear picture.
he wrote songs for em and they were under the label at the concerts.
Big hits company buys were more of a merger than many other companies.
Lovelyz for example were never at SM town. Nor have i seem Mystic artists.