Just hypothesising, but perhaps the Argyll organisers realised they had to make the Dunoon town centre stage accessible to spectators if it were to run at all, and also realised that they wouldn't be swamped because the rest of the rally is in a fairly remote area. They have a supportive relationship with the local tourist board/council too. The Scottish and Grampian are much closer to large population centres and maybe more at risk of negative reaction from local councils and nervous residents if they attracted a load of speccies?

Whatever the case, I hope things are clearer before Mull because there is no way they can try and run that with a No Spectator policy.