The route you're talking abt is not feasible to run Shatabdi Exp.If that would been the concern,then the Railways would've run Shatabdi from Lucknow-Gorakhpur,Chhapra-Hajipur,Barauni-Chhaprra,Haridwar-Lucknow,etc....the main thing is the track is not capable of handling the Shatabdi Speed.