Walking through the City of Brass with a lesser artifact crown, plus two fucking IOUN STONES orbiting your head like you're fucking Felandrial Morgethai, attracts more stares and avaricious glances than just the artifact crown.
Nobody tries it; at least, not yet. Everybody in this part of Fommok Madinah is a few millennia old at least, and didn't get to be that way by directly attacking unreadably Mind Blanked adventurers with a lesser artifact and two fucking Ioun stones.
In time, they succeed in coming across a larger building, a mighty brazen slave-market, which also advertises in passing that it grants Wishes, up to five Wishes in succession; as is one way of advertising that this business is worth the attention of at least five noble Efreet.
In retrospect, you wouldn't actually expect to find a shop that was just five noble Efreet waiting around to perform a service whose custom they might receive once per year if they were lucky.