"Well in short, there was no air conditioning. And we weren't royalty." Bucky was still taken back at how they had kept a lot of the core portions of what used to be baseball intact, while completely expanding on the opportunities to improve seating and overall experience for the fans. A lot of his baseball games had been seen from behind a fence, or maybe--if he could convince Steve--getting inside from said hole in the fence. He shouldn't have been surprised but Bucky was trying to enjoy taking in the new experiences and enjoying them for what they were.
A part of him still missed the heat, dirt, and lack of assortments at their disposal. Just enjoying an experience of the game in the hot sun with the rest of the crowd, getting rambunctious together for their chosen team, scraping nickels together for a hotdog to split.
This was just another experience in and of itself. He knew Steve was trying to incorporate him in more than just a day to day job and the isolation of their apartment. Bucky appreciated it, and didn't mind because Jane was just one person. And very calm and sweet at that. Plus, he wouldn't argue about all the extra hotdogs. "Thank you for inviting us."