7 ounces is like 200 grams that is a big deal especially when you are already weight depleted. This is Bad on Rubio for failing to make weight as he is supposed to be a pro.
I don't think anyone was ever under the impression that the weight would make a difference as far as the outcome was concerned. The only thing it would have effected was the eligibility of the fight to still be a middleweight title eliminator.