It is true that local events can drastically transform a trip, but the idea that they are always the decisive factor in destination validation is a bit simplistic.
Here in Senegal, many families travel based on school holidays or available budget, which often takes precedence over the presence of a festival.
If an event like the Grand Magal of Touba causes prices to soar, a family on a tight budget might choose to postpone their trip or change destination to avoid costs.
The middle ground is to recognize their impact while keeping in mind that practical constraints and travelers' flexibility are often the true arbiters.