One advantage of the smaller communities (in speedway terms, Workington, Berwick, King's Lynn and maybe Poole) where there is no big-league soccer in the towns to distract attention is that the speedway clubs -- who can boast "international stars" in virtually every meeting -- are usually the biggest sporting attraction in town.
Also, in these smaller communities, even if people don't attend, I believe the whole town knows about the Comets, Bandits, etc. They know speedway exists there.
Whereas in the cities, in Glasgow or Edinburgh, if I mention speedway to people the usual reaction is "oh, is that still going?"
The downside being, there are less than 30,000 people living within 25 miles of either Workington or Berwick. There are about two million within 25 miles of Glasgow!