nostr:npub1c74n52sngtmceu96gxms7lsfcdz3gqsfla9swcdgt7wc0qw684zqfe2cj2 doesn't sell ON nostr, but its a bitcoin-only company and is designed specifically for nostr users (and features many nostr authors)
Discussion
And my boy nostr:npub1y69efz664d96krj5xrhync707ythdncc8hunkvs4n7t8pm25zj2snkwae6 advertizes a Bitcoin AND Monero service on Nostr.
But enough with all this pointless evidence. It doesn't matter who shills what on Nostr. Nostr should be a microblogging platform, not a cryptocurrency shilling platform.