Buffeted by a cold October breeze, the banner on the construction fence still says "Lowertown Ballpark Opening May 2015." Workers are too busy welding steel and pouring concrete at the new home of the St. Paul Saints to switch it out for a ­banner reflecting its new name, "CHS Field."

Last month, a jazz band played, the purple mascot romped and executives in hard hats celebrated an odd partnership: an agribusiness giant lending its name to the latest neighborhood-revitalizing, taxpayer-fueled urban ballpark.

There was one subject that none of the dignitaries wanted to talk about that day: What CHS was paying for the naming rights to a city-owned ballpark.

That's a private matter between the Saints and CHS, we were told.

Actually, it isn't, because anything the Saints earn over $500,000 from the naming rights deal will go to the city of St. Paul, so it can pay off the loan that it made to rescue the project from an $8 million funding gap. Just about all the public knows about the agreement is that the size of CHS's payment is based on attendance, and that CHS is allowed to use the ballpark for big parties when no one's playing ball.

Nothing should surprise me any more about the hubris of sports teams and their corporate partners that receive showers of public money. In fact, I don't blame CHS or the Saints for wanting their agreement to stay under wraps.

What I can't understand is why the politicians go along with it.

It's helpful to understand just how big the public stake is in building a $65 million minor league ballpark in downtown St. Paul. More than 82 percent comes from taxpayers. The largest chunk, $25 million, is from a state economic development grant (a consolation prize from Gov. Mark Dayton after the new Vikings stadium landed in Minneapolis). The city is kicking in $21 million, in addition to a $6 million loan. Another $3 million comes from state cleanup grants and loans.

It works out to about a $100,000 subsidy for each full- and part-time job created.

The city of St. Paul will own CHS Field, but will pay the Saints $50,000 each year to maintain it. And if the team is sold within the next seven years, the city would get a cut of the sale price.

It's hard to imagine much closer ties between the government and the Saints short of the ballplayers going on the public payroll.

City leaders, for now, don't sound especially concerned that some aspects of this deal happen behind closed doors.

Kathy Lantry, the City Council president, said the arrangement will become obvious once the ballpark opens and the money starts flowing to the city. People may have to do some algebra, she said, but it won't be very hard to figure out.

"I don't know that the public necessarily cares about what the deal is," Lantry said. "I would guess that what they care more about is how much money we get for it."

Mayor Chris Coleman "doesn't disagree that the details should be made public," said Tonya Tennessen, the mayor's communications director. Tennessen said the mayor himself doesn't know those details at the moment. The city made sure that it had the authority to audit the Saints books to ensure it's ­getting its fair share, she said.

Dayton isn't standing up for secrecy, either. His spokesman, Matt Swenson, said Thursday: "The governor believes the terms of the agreement should be made public."

So what is the governor doing to make that happen? Not much, apparently.

Tennessen pointed out that the governor's administration had a chance to weigh in on the ballpark use agreement, which allowed the Saints to negotiate the naming rights.

Perhaps the Saints ballpark will turn out to be a great public investment, accelerating Lowertown's revival in the way Target Field has enhanced the North Loop. With such deference by politicians to corporate secrecy, the public will never know if it got a good deal.

Contact James Eli Shiffer at james.shiffer@startribune.com or 612-673-4116. Read his blog at startribune.com/fulldisclosure.