Simpler: the traveler's goal dictates the importance of local events, not the other way around.
For some, a festival is the goal; for others, it is an obstacle to avoid.
Instead of integrating each event, focus on the main priority of the trip.
If your goal is relaxation, the Tulip Festival at Keukenhof, although popular, would be a constraint, not an advantage.
The parsimony in planning reduces unnecessary variables.