Its because the crowd is totally blah
On ice sound has gotten better but the times the refs click their mic on and there is banter of an FCC/CRTC questionable type has to be a record.
That said, I would pay for a feed that allowed me to turn off the PBP and color folks to just hear the on ice sound. There is something soothing about skates on ice, pucks hitting the boards, the sounds of contested ice.