Kenny Chesney in 2012. (Josh Sisk for The Washington Post)

The army of tank tops and flip-flops arrived by bus, boat and truck. Their battle cry was the crunch of an empty beer can, the belch of a full belly. Some had tickets to the main event. Most were just there for the party.

Kenny Chesney, the man at the center of the drinking-palooza, likes to call them his “No Shoes Nation.”

But as soon as he finished singing, they all needed shoes. Knee-high boots, preferably. Because Chesney’s fans left so much trash in Pittsburgh, people had to plug their noses just to make it through the parking lot.

“I have never seen this amount of trash, ever,” one attendee told the Pittsburgh Post-Gazette. “What are we, savages?”

The morning-after headlines were as potent as the hangovers:

Dozens Hospitalized at Kenny Chesney’s Pittsburgh Concert

Kenny Chesney concert goes horribly wrong

Were You One of The Dozens Arrested at the Kenny Chesney Concert This Weekend?

About 48 tons of waste were left in the parking lot, according to the Pittsburgh Tribune-Review. Almost 100 people had to be seen by emergency medical personnel, and 37 of those people had to be taken to a medical facility. Before the Saturday night concert even started, 36 people were cited for underage drinking around Heinz Field stadium. Others were charged with ticket robbery, public intoxication, trespassing and simple assault.

You might expect the locals to be outraged. But as a Post-Gazette headline announced, the city was actually “very pleased.”

“There was superb inter-agency cooperation. Everyone worked very well together,” Guy Costa, the city’s chief operations officer, told the paper. You see, dealing with Chesney fans is a Pittsburgh specialty; the country star has been making pilgrimages to the city since 2005.

Every time, fans arrive days and even weeks in advance to set up boats and tailgating headquarters along the Burgh’s North Shore. In 2013, so many ready-to-party fans descended on Pittsburgh that the lines of standing people waiting to enter the tailgating parking lots backed up traffic in the city. The lots were forced to open early, and at least 10 fights broke out within hours. One was captured in a YouTube video in which more than a dozen men punch, shove and pull each other to the ground as discarded beer bottles rattle on the concrete beneath their feet. That year, 73 people were arrested, 150 treated by medical professionals and 45 taken to hospitals.

Some feared the debacle would mean the end of large events at the hallowed Steelers’ stadium. But the Chesney-fest only grew. This year it was accompanied by a Billy Joel concert on Friday and a Weezer concert on Sunday. Old Dominion, Sam Hunt and Miranda Lambert opened for Chesney. About 40,000 people bought tickets for the show and thousands more showed up just to tailgate.

Chesney hasn’t made any statements about the trash, arrests or hospitalizations. He typically thanks fans from each city on his “Spread the Love” tour on Twitter, but hasn’t sent out any messages since last week. As dump trucks hauled the broken bottles and crushed cans to far-off landfills, Scott Mervis, a music writer for the Post-Gazette, contemplated what Chesney could say to his fans.

One way to start: “Hey, this is Kenny, spread the love, not the garbage.”