This manager should be fired if Target truly values making money. Not even because of his stance on the police, but because he's clearly more interested in his own beliefs and feelings than those of his employer and team. It's terrible optics for the company who's already been dealing with quite a bit of controversy lately and it's bad for business.
Most of all it's petty. This was a fundraising event to help families who were having financial difficulties get supplies so their children can have the tools they need for their education. To try and stop what's very clearly a positive cause in your community is the epitome of a self-serving asshole.