The way they did it made suspension of disbelief impossible, and it's necessary for fans to have that. We can watch them throw people off ladders, put people through tables, etc because we know that, barring an accident, they're going to be ok, even in a match as extreme as this one. But there's no way to safely light someone's whole body on fire during a match the way they teased doing, so we knew it wasn't going to happen. They might have been able to pull it off with the help of a Hollywood special effects team and a stunt double, but that wasn't happening here.
And, on a story telling level, now the heels look like heroes and the babyfaces look like monsters.