Nearly all companies "steal" from their employees. If the company makes any profit whatsoever, that is surplus value which has not been paid to the employees who generated it.
Marx has been dead for 135 years, and people still parrot his confused ramblings without thinking. Amazing.
It is common to refer to this as unearned income because it is income received by virtue of ownership not work.
Investors and management are intertwinned and blurry. Smaller businesses usually have them the same and larger ones must compete with the alternative of starting ones own and thus pass down dividends. Even the most hands off "useless idiot heir" has an indirect management role via who they ultimately choose to support and what they do with it.
Investment has a role aside from funding that they engage in by driving efficiency, expansion and the dreaded counterpart of contraction to match with demand.
We have empirical evidence that while management and ownership often do in fact do useful work. Look at how farm appropriation has ended in reduced yields instead of increased as one would expect when farmhands gain the benefits of more ownership. Instead their production plunged and they started experiencing increased crop failure. Which brings to mind the related fallacy that farming is simple.
It is true that management and ownership and investors are often overcompensated and worryingly self perpetuating at the expense of others - but they do in fact have a legitimate claim to profits.