Answer: they're not. The vast majority of Christians don't give a shit about the holiday's pagan roots or all the spooky imagery that goes with it because they're well aware that it's all harmless fun. The most you have are your obnoxious fundamentalist types from extreme fringe sects who have problems with everything. And you know what? I hardly hear a damn thing from them every Halloween. Unlike the antitheist lefties, who every year update their list of costumes you're not allowed to wear.