By that logic capitalism with its constant competition is highly wasteful.

Capitalism does not really involve more "competition" than is inherent in human nature anyway. What it does WRT competition is precisely to try and ensure that it leads to favorable outcomes, largely by making property rights more well-defined and more easily protected. ('Tragedy of the commons' scenarios result from competing over an exhaustible 'commons' for which neither property rights nor customary access rules are defined.)

it's a rule imposed from above by governing bodies which are mostly interested in selling the performance for money.

You might be assuming that professional athletes are not collectively "interested" in having their performance be popular when it gets sold for money. The opposite is very much the case. Yes, much of the appeal of sports is in its "fair contest" aspects - we would not be happy with a "pure entertainment" surrogate where the outcome of every contest was actually pre-determined in advance! But of course every sport has its rules.