That's a good data point, the market is surprisingly small which could account for lack of competition. But the last annual report has the ticketing org alone at 37% EBITDA margin [1] (they call it AOI). No expert on benchmarking this # but wouldn't say they're not milking it.
[1] https://d1io3yog0oux5.cloudfront.net/_6fc34851c72a6087b32b93... p47