I never went to a Ringling Brothers circus that was in a tent, and I have went to them in the 1980’s, and every year since 2007.
They resumed performances in a tent in 2009 - selected locations only:
http://millefiorifavoriti.blogspot.com/2009/07/if-you-read-my-prior-blog-post-i-asked.html
Yes, I saw the B&B circus years ago in a minor league baseball ballpark. No tent in sight.
My father told me when he was a young’n back in the 30’s the Elephants walked past his house on their way from the train station to the fairgrounds and if you helped with the tent raising you got a free ticket to the show.