As a Lutheran, LCMS member, we tend to be demographically: rural, small-town, or greater-metropolitian in nature. Many alternative lifestyles are frowned upon and aren't acceptable.
Most Satanist congregate in larger numbers within larger cities, obviously closer to the media as well. Alternative lifestyles and larger quantities of various religions are the norm, especially towards the downtown areas.
I'm not so certain your data doesn't have demographic biased data. Also, we Lutherans consider a congregation over 1,000 to be a mega-Church, so I don't think a Satanist would feel as effective in their efforts to achieve public disruption.
I also believe there are some with Inquisition retribution, that's more easily directed towards Roman-Catholicism than what's generally associated with other denominations. The Eucharist is attacked because of what it means to Roman-Catholicism, not because of what it means to Satanist.