It's entirely possible that they lost money on this, to be clear.
I would imagine that most of these entities have done a full-blown analysis of what their profits would be at different prices, and chosen the ones they have for sensible reasons.
Edit: also, this is not an apples-to-apples comparison, given that you're looking at a team coming off a Super Bowl visit, which would generate increased demand for all kinds of things.
The article just says that sales revenue went up by 16%.
But, food and labor costs must have risen. If you cut the price of hot dogs in half, and your revenue goes up, you're selling more than twice as many hot dogs. So your food costs will at least double. (I imagine that the stadium is already getting the best volume discount possible).
And you need more workers to sell more hot dogs. (Note that the article says there are "65 percent more points of sale and 1,264 more beer taps" - someone needs to work at those.)
The article annoys me, a little bit, because it makes it sound like this is a clear winner, and other teams could learn something from the experience. But in my experience, the pricing departments of sports teams and their affiliates are incredibly savvy and getting more so all the time, and I'd be shocked if this was a surprise to any real experts in the industry.
And indeed the writer does slip in one instructive line: "the reaction by the rest of the sports world has, for the most part, has been to ignore it. Few teams have sought to replicate the model..."