I think that's ok. (Or they could use a Dash-8). I flew WN from HOU-AUS and it was 26 minutes in the air, 45 from gate to gate. To me, that's the biggest waste of jet fuel, and the plane wasn't even near full.

I fly to and from CLT-ROA on Dash-8s and it's just fine by me. It is probably a 30 minute trip on a ERJ or CRJ but it makes sense to me for them to fly a D8 in there, plus I get a more comfortable ride.