Ted Nugent loves the great outdoors and often writes songs about it. In "American Campfire," he celebrates a great tradition in nature: gathering around a campfire with good company. He probably won't be toasting marshmallows though: Nugent famously eats only meat that he kills himself, so there's a good chance he'll be cooking something he hunted.
The line, "Let me buy you all a beer," is a rare reference to alcohol in a Ted Nugent song. He's anti-drug and doesn't imbibe, but he also knows that many of his fans enjoy a cold beer with a warm campfire, so he's happy to buy.
Nugent is known for his outspoken political rants, but his songs generally steer clear of politics and often cover topics you don't hear about very often, like campfires. Much of his Detroit Muscle album is a tribute to his hometown of Detroit.