If someone told me that the denim pants I wear 99% of the time suddenly meant support of some cause I'd probably change too or rebuke the statement outright, regardless of the cause. I understand the importance of banners to signify one's cause but placing banners on innocuous things and expecting everyone to go along with that is rather conceited.

It's probably unintentional, but these types of cutesy movements are actually pretty nasty in how they just sow division. When you turn an unavoidable mundane action like wearing clothes into a symbol of support, there's no true 'abstain' option, essentially forcing people to pick a side.

It's "you're either with me or you're against me" in non-verbal social pressure form.