[scandata]

It might have been a waste of time in this case, but we know that this case made it to the desks of some higher-ups. Every time this happens it's another pebble in their shoe, and another voice telling them not to get too greedy. Hopefully it will make them think twice before implementing further restrictions, or at least be more explicit in what will get your warranty voided. If the agreement actually listed a catch can as a violation, the OP (all of us, actually) wouldn't have felt like GM just looked for an excuse to void the warranty.

It's like when a cop abuses his/her authority. One person complains and it gets swept under the rug. Enough people complain and someone takes notice. In this case, if this happens too many times, GM will get a bad reputation, and someone on the fence between a Camaro or Mustang might go with Ford. Several here have already said they'll check the competition next time. Keep fighting the good fight!