An article in the Financial Times about Taylor Swift’s Reputation concert tour made the following three points:
1. “Instant sell-outs have become a rite of passage for big stars, as scalpers use software to buy up tickets the moment they are available online.” 

2. Most of Swift’s concerts on the tour didn’t sell out.

3. But Swift’s “strategy appears to have paid off.”
a. What are ticket scalpers? What has to be true for ticketing scalping to be profitable for scalpers?
b. What was Swift’s strategy for selling tickets on this tour? How did she benefit? What risks did she take? How else might Swift have increased the money she made on the tour while reducing the money scalpers earned?