Hacker News Reader

The code is rolling so you can't use a screenshot to enter the show. This is to stop ticket transfers outside the system.

The ticket stub is animated so you can't use a simple screenshot to move to a better location once inside the show.

I wonder if they want to prevent reselling or at least require that it goes through their app? (I think this is a bad thing for them to do, just trying to think of the motivation).

My guess is, you're right, it's to force your use of their app. for data harvesting reasons?

Could be that too.

Human beings are checking those tickets, and movement is proof of liveness (and not a screenshot you and 25 friends are sharing). Many ticket checking systems are not connected to the internet and cannot/will not check if it's already been used. Many of the motion enabled codes are also basically working in the same way as 2FA codes: your ticket is given with a public key, usually unique to your device, and rotates every minute. Allows them to ensure that the ticket is up to date, not forged and signed properly.