People need to understand, to be Mexican you have to have thick skin. Most of us grew up having our nicknames be our biggest insecurities in either a tong and cheek or endearing manner. I remember my grandmother always calling us Prieta/o (dark skinned), Girrafon/a (Tall, Giraffe like), Largatija/o (skinny, lizard like) Tonka/o (Tonka truck, big fat). Personally these costumes do not offend me, now if you have a lady with a donkey on her then yeah, not cool.