Not getting premium channels in HD

I just started with Xfinity yesterday and am having problems accessing HD versions of HBO and Showtime. I get some spread out over a large channel range, but not all of them are HD (but when I look at the Xfinity stream app they are).

I’ve had two very kind technicians out to my house but the answer seems to be “yeah, that’s the way it is.” I guess I’m having a hard time believing that. Surely if they are HD on the steam app they exist as HD.