History
It's a testament to the team's history of success. The championships during the 60s might be the best Dynasty in the history of the NFL. There are plenty of teams that have been around as long as green bay (not nearly as many today), and not a single one has won more championships than Green Bay. And if it's not that big of a deal, then why don't the Steelers and Bears have more championships. They're both storied and been around a while.
My favorite is when people try to say the first two super bowls don't count. You can't say that without drawing a line somewhere-- whoever says that is beginning to run down a slippery slope. If you say Free Agency, then the cowboys, 49ers, Steelers and Giants suddenly have a lot less clout in the championship discussion. It's funny because Green Bay has won a Super Bowl within the last 15 years, but also because half the teams in the league have never won a super bowl let alone three.
Most of the time when I hear this its from a Bears or Vikings fan which is extremely hypocritical. Sure the patriots might have us beat in the last 10 years, but history still happened and green bay hasn't done too bad in that department in the modern era.