The first version of the tour carried a more complicated set with a special raked, miked floor similar to the floor that was used in the Broadway and London productions. The mics under the floor enabled the tapping to be amplified. But once the miked floor was done away with, other means had to be utilized to amplify the tapping.
Since this fits with the other questions that have been asked about the show, I will move your question to the section with the other questions.
PS: Welcome to the forum bebilly 2013.
