That’s the angle the photo is taken that makes it look closer then it actually is. Here is one from a different angle. https://www.facebook.com/startrax.info/photos/a.1563229817231416/2806349479586104/?type=3
I think it depends on the distance between the track and spectators, at Belle Vue and Stoke where there was a greyhound track in between, the 6ft catch fence wasn't required.
It's been over 23 years now, the last season in 1997 they won the league and the crowds were poor then, I cant see there being an appetite now. Maybe for one off bigger meetings.