You are thinking about check in at the airport, not the TSA line.
Airlines are for profit businesses. Bi fly four or five times a year. I fly coach/economy. I am in the 80% of their customers that provide marginal profits. The other 20%, the high value customers are the bread and butter to their company.
Yes, they treat those customers better. And they should.
They get expedited check in. They get pre boarded. They get upgrades. They get free stuff all around. They pay tens of thousands of dollars a year to the airline.
You and me? They make about 5% profit off our $400 ticket. We get treated like the cattle we are. No company is going to go out of their way for a marginal customer.
Yea, the last time I flew was pre TSA.......