Spite? Honestly? I am sure the whole pull-down in PIT was nothing more than an evil corporate empire putting the hurt on politicians and media types that liked to dwell on the negatives. The good folks of SW Penn. need to stop taking this so personally.
PIT-FRA went away because it competed with CLT & PHL to FRA, and someone dug through the data and figured out enough people would stay on US with a connection to the point they could use the plane somewhere else and make more money with it. 7 Bayer executives on one day do not a profitable daily transatlantic flight make. If US lost Bayer's FRA business to UA I'd fault the sales department, not the lack of non-stop service.