People have been protesting this company for decades. "The Walrus and the Whistleblower" is a great documentary on Marineland, following the story of a local activist who spent years in legal battles against Marineland. Nobody is going to stop fighting while there is still any opportunity to pursue justice for those animals.
It's too bad you feel like the battle is already lost, but I don't think that's any reason to stop fighting and surrender to something you know is wrong.
I block freely. My time and attention and mental and emotional bandwidth are limited resources, and to the extent possible I intend to spend them carefully.