There are lots of platforms for ticket sales and venue management. That's how they run high school and college events, local theaters, etc. Ticketmaster is doing something completely different.
Also is First Come First Serve really fair? Some people have more time at hand to keep refreshing the page until the tickets are available.
Upon arrival at the venue you show photo id and a sheet of DIN A4 paper containing the hash and seed, and the Ticket Man will verify.
Side joke: One of the German ticket sites, maybe eventim, stated on the PDF that it must be printed on DIN A4 paper.
Not all artists can do as many shows as the market demands.
People should instead consider the vanity of thinking they absolutely need to see a certain artist perform live on stage.