To call the events initiated by Christians at the Pentagon or elsewhere "acts of worship" seems to me somewhat wide of the mark. Too public, too political, too endangering, too dramatic for that, a rather gentle classification.
Games certainly, celebrations - but serious, and played for keeps. After all, one can do an "act of worship" in the closet. Secret commerce with God is sometimes commended, sometimes practiced by Christ. But this is another matter entirely.
The atmosphere, the circumstances, are of import. Not only what you (plural) do at such places of ill fame, but the spirit, the accompaniment, the aura, sense of life you summon there.