> Many people invest for ideological reasons, myself included, and that's fine.

Sure, but I'm under the assumption that many people, yourself included, are conflating "buying some company stocks" with "investing".

To first order approximation, it does not benefit a company that you trade stocks on the market once they have been emitted, any more than it benefits GM if you opt to buy a second hand chevrolet.

So the support is symbolic only.