Never judge shop fish by their colors. Colors are easy to loose and just take time to gain back in a proper low stress environment. There are certainly low quality-low color fish out there, but just because a fish is low color, or even colorless, don't assume it is from poor stock.
When I first ordered my panda garras online they looked like nothing, which is what I was expecting. Even though healthy, mine took a couple months to regain their true wild colors. Its similar but not as long with fish like sparkling gouramis, and ember tetras which often look mostly gray in the shops.
These are the same fish from my tanks.