I see a big difference. Low wait times to me at least, means lower than normal park hours and these times, while longer than I like and longer than I think they should be, are indeed lower. Little wait means just that...little, not much at all, if any. It's admittedly a fine line, but as can be seen in this thread, the opinions of the very same event on the same date are all over the map. Even with the heavier crowd levels at VAH, it would seem it can be managed- riding the most popular rides at the end of the event is the best way to go. At both events, the popular rides are going to be busier getting the non-party people through the line. Personally, I think there should be a buffer- but there isn't, so we make adjustments. We absolutely lucked out when they added an AH event to our arrival day. Had it only been the VAH offered later in the week, we wouldn't have done it. We're not interested in villains, we're interested in rides during AH's.
It's really up to each person to do their own research. It wouldn't take 5 minutes to look up both events and find out that VAH's are more crowded. I don't think it's even close to false advertising. Still, anyone who wasn't satisfied with the event should contact Disney and let them know. But I can tell you, all the complaints I've made about the holiday parties have fallen on deaf ears. As long as it's a minority of people and sales don't suffer, they have no reason to change.