[aktenlage]

Nah, you are defending something that is based on the right to own property (and do whatever you like with it), but may nevertheless be shitty behavior. Just because something is legal and the legal basis is important (in your opinion), doesn't necessarily mean it is ok behavior.

E.g., being rude isn't forbidden, the freedom of speech is important, so is the right to express your personality. But lecturing the affected person about these rights may not be the best reaction when they have been insulted by someone.

I think the main point to discuss is not the rights, but whether the owner of a company should act more responsible, even if he is within his rights. And that's also the point of the OP.