What is a Desert Raccoon though? Sand + Ichibi = Animal that could not survive naturally in a desert.
In any case, if he wanted to be politically correct, Jiraiya's frogs should have been in the Mist, not in the Leaf. 

Though, for the most part, the rest of the summonings do suit the environment. Just as ninjutsu typically suit the environment. 
It's all about preference really. I don't think it is a big deal either way.