Must admit I don't go to them as it's not really my thing but surely it's more for the general public with their kids etc who want a day out rather than enthusiasts.

Whitley (North Tyneside), Durham (North Durham), Bishop (South Durham), Metro Centre (Gateshead / Newcastle), Seaburn (Sunderland) are all quite a distance from each other and serve different areas of the North East. The GP from Durham aren't going to travel to Whitley Bay or the Metro Centre to look at some buses and vice versa.