People typically purchase show tickets in advance in order to secure their spot and avoid disappointment. For popular shows, tickets may sell out quickly and people want to make sure they get their desired seats. Additionally, many people like to plan their travel around specific shows or events, so buying tickets in advance allows them to better coordinate their schedule.
However, with the outbreak of COVID-19, many events have been cancelled or postponed. This has caused some people to hesitate before purchasing tickets, in case their plans end up changing. For example, someone who was planning to travel to Las Vegas for a concert might decide to wait until closer to the date to buy their ticket, in case the event is cancelled or someone from their party has gotten sick and cannot travel.
Overall, advance purchase of show tickets is the norm, but people may be more hesitant to do so in light of the recent pandemic.