I think this (low effort posters) rather signals to me that they have the right priorities. A true professional poster would tell me that it's some commercial cash grab instead of real local enthusiasts making something normal.
I am inclined to agree. Small community organisation cannot afford to pay a professional designer. They might be lucky and have a talented volunteer, but in general its a waste of limit resources.
To me it's the opposite. If the poster is something typed up in Word, I know the Farmer's Market is the real deal. If it's AI generated, I immediately get Temu dropshipping vibes.