That $50m is the amount decided to reach their audience. Increasing the donation won't increase the reach...
I remember recently a pizza chain in my province decided to stop all their ad campaign for a month and give the amount they would have spend otherwise to people. Hey if it works for Mr. Beast, it could work for them right? I saw it on Tiktok so a good platform to allow organic sharing, well a week later I started to see ads about it on Facebook... they didn't reach their audience.
So yeah that spending is for their ads, they are going to spend it, it's there for a reason. Believe me, if they could lower it in some way, they would... that's called business. Is there really anyone in the world happy to pay ads and that doesn't do anything to try to lower that cost?
At best they could avoid the bad press from r/antiwork (does it really matters? how many views did that get versus that $50m ads?), but I got a feeling that they would still complains about the fact that they spend more in ads than in the actual donation.