I could see someone feeling slightly cheated if a foot long isn’t quite a foot. That being said, the proper remedy is not to buy it next time.
Perhaps you didn't read the article. All of the sandwiches came from the same AMOUNT of dough; The actual shape of the individual loaves varied depending on how it was shaped/baked.
Or, are you one of those who gets upset when you find your box of cereal is only 2/3rds full (ignoring the 'contents may settle' label)?
Of course, subway could "stretch out" the dough - making sure that each loaf is equal to or greater than 12 inches, but is it really necessary? Would you feel better if the sandwich was >12", but looked like:
Of course not.