Shaykh Abdul-Muhsin Al-Abbaad was asked:
“A question came in regards to mentioning this supplication in the storefronts, or groceries, or supermarkets. Is it sufficient to mention [the supplication of the market] in the markets of our custom nowadays or is for the general market?
“In any case, if a person says it in a place of buying and selling, even in a specific market, and he says, ‘Lā ilāha illallāh, waḥdahu lā sharīka lahu’, no doubt this is what is necessary for a person to do because the first affair is easy. If he goes to a place of buying and selling, whether a specific market or general market [, he says the supplication]”. End translation. [Sharh Sunan Tirmidhi no. 378]
Faisal Ibn Abdul Qaadir Ibn Hassan