It depends on the sticker. Like I wouldn't put an Element sticker on an Antihero deck (or any other deck for that matter) but I would (and have) put a Scumco sticker on an Antihero deck if it's a Kanfoush or black and gold because of the Pittsburgh connection.
Obviously everyone is free to sticker as they please and show support for anyone they want to, but for me personally there has to be a reason for it beyond just supporting the company or liking the sticker and I can definitely understand why it bothers some people. I have a weird thing too where if I put a bones/spitfire or indy sticker on a deck I feel obligated to only ride those wheels or trucks with it, even if it's to my detriment.
For an activity thats supposedly all about freedom and individuality and creativity skateboarding has so many little rituals and unwritten rules governing what's acceptable lol.