Because it comes off as spiteful more than anything else. Everyone is talking about how the average consumer can surely afford .99, but conversely giant motherf-ing ATT can afford .99 as well. This comes across as taking someone's ice cream and then licking it once before giving it back. It basically feels rude. "We agreed to a free pricing structure, we let Apple tout it as a free pricing structure, but now we're gonna tack on the measly sum of .99 because we're ATT and we can." If ATT had a history of doing what's right for the consumer and not engaging in petty pricing games, I suspect people would be more likely to be ok with it. However, ATT has a history of engaging in very anti-consumerist behavior just because they can. They've earned the ill will that is directed at them.
