

There are four imperatives you could use here:
- kauf or kaufe - used with “du” (informal, singular)
- kauft - used with “ihr” (informal, plural)
- kaufen - used with “Sie” (formal, sing. or plural)
All four would be grammatically correct here, but using the informal forms towards someone who you aren’t acquainted with sounds a bit too bossy, too rude. So I’d recommend using the “Sie” forms instead.
I also recommend changing the verb. As @superkret@feddit.org said, the Nazi used the slogan “Kauft nicht bei Juden” (don’t buy from Jews), and the association is still strong.
Just listen to Pitura Freska, my peers. We need a black pope.
I’m not Catholic any more, for decades, but it was nice to know the pope was from my “turf” of the world instead of yet another European. Plus he was considerably humbler than other popes, the instructions for his own burial are a good example. (In fact a lot of people I know get surprised when you mention that he was a Jesuit instead of a Franciscan. Not just because of his papal name - but because all that “think on the poor” discourse is extremely Franciscan.)
His Easter 2025 message is worth a read, regardless of religion.