Given that Carpdime has depicted Buttercup being able to pace with his owner, I think its safe to say there’s quite a bit of difference between the average fluffy and a street fluffy. There’s also the idea that there are different breeds of fluffies, like how Candy is of the “Waggytail” breed, which is based off how Waggytail drew his fluffies to be more agile.
Think of it like how certain fluffies are more expensive than others, and from there, there might be some money in breeding more “pure” or exotic looking fluffies over rare ones. But yes, at least in the setting of the Avocadoverse there’s huge differences between a street fluffy and a domestic.