Say there are 5,000 season ticket holder accounts in 2020. And they give 5 Blue Cards to everyone. That's 2 seats per card. 5,000*5*2 = 50,000 / 17 Home Games = 2,941 extra attendance per game. They're just doing this (aside from getting new fans potentially engaged) to artificially inflate attendance numbers.
If it adds even 100 new fans to the team next year, it's worth it. Our active fanbase, for whatever reason, is dwindling. Fans aren't coming out to the stadium to watch one of the best teams in the league. Their job is to increase the fanbase. This is an attempt at doing that. We all need to look at the bigger picture. The fanbase is not growing. The fanbase needs to grow. This is an attempt. We should all cheer that they've got some outside-the-box thinking.