Halloween and Christianity

Nowadays, some people are pointing out (with an attitude somewhere between "holier than thou" and "grumpy") that they don't celebrate Halloween. This is because it is pagan, they say.
One question is, why are we against the pagans? If it is because we are Christian, didn't we already win this war a few thousand years ago? To seek to remove all evidence of paganism from our Christian lives, such as declining to celebrate Halloween or declining to have a Christmas tree, is to pursue an inquisition. To relentlessly and savagely examine every trace of our modern lives for remnants of a time before Christianity existed, and work to purge these traces completely away, is not the spirit Jesus brought to the world. It's the spirit of anorexia. And of hate.
Another question is, what's anti-Christian about Halloween today? The answer is, nothing. To dress as a monster isn't to uphold the monster as right, it is to subdue the monster by controlling it. Evil cannot be eliminated, but it can be controlled. In the real world, Halloween is about community (visiting your neighbors and getting candy, like a blessing, really) and creativity (costumes and decorating the outside of the house).