Not USA, but here are some of the stats about Estonia's most popular courses.
Here in Estonia and in multiple other European countries we use
DiscGolfMetrix to keep score. "Rounds played" is public info, here are the stats dating back from today to 12th December 2022.
For example, Estonia's busiest courses usually get around 13-16K rounds per year and I think around half the people don't even keep score if not more.
In fact, during summertime the Kurna disc golf course (one of my home courses), is pretty much a "no-go zone" after 3-5 PM for me, because there are just WAYYYYY too many people. Usually 5+ groups waiting on the first pad + every teepad full of players.
And I've heard that it's even "worse" in Finland, especially in the Helsinki area. People waiting for hours just to play a round... Even though there are plenty courses, around 850 courses in Finland and 250 in Estonia, it goes to show that disc golf is very popular in both countries and there are just too few courses near the big cities.
Here are the 2022 Estonia's most played disc golf courses:
In addition, plenty of Estonians and Europeans use UDisc and I think Finns and Swedes even have their own scoring systems, so a lot of data across multiple platforms, but nobody is putting it all together and showing it as one. Hence the reason why most of the bigger European disc golf countries don't show up on the UDisc stats.
For example, Valbyparken Disc Golf in Denmark is
one of the busiest courses in the world, around 41K rounds back in 2022.
PS! Fun fact! Europe had 20 120 active PDGA members at the end of 2022, 21.3% growth rate compared to 2021.
Here's "Disc Golf Seasonality in Estonia from 2017 to 2022".
Estonia's Disc Golf in Numbers (2022):
If you like to read more about Estonia's & Europe's disc golf scene, check out this blog post -
Estonia's Disc Golf in Numbers (2022) | Disc Golf Fanatic
UDisc list of the most popular disc golf courses in every country: 2022 -
The Most Popular Disc Golf Course In Every Country: 2022 | Release Point - The UDisc Blog