It's all part of the same framing. It's important the targets of these newsletters feel the same danger, the same crisis, the same "we're running out of time" motif that pervades all of the right-wing social issues. The biggest enemy of these groups is the thought, "Live and let live."
The right-wing builds up a constant sense of invasion and fear: including immigrants, terrorists, gays, atheists, communists, etc. Some of these are realistic and real fears, if sometimes blown out of proportion, some are not. But what matters to the right-wing machine is communicating that sense of impending doom, that idea that if you don't donate and vote Republican right now, that the evil-doers will come any second now and take away your cross, make your kids gay, outlaw Christmas, and blow you up. All at the same time. These constant barrages of, "Corporation XYZ isn't sufficiently Christian-affirming" are just one of a thousand ways that the right keeps people from thinking that things can ever, ever, just be left alone. If people truly started acting in, let alone believing, a "Live, and let live," approach to life, all of this fear-mongering would be useless. And that's exactly why they can't let up. Not for a day, not for a second, not when there is fresh outrage to be served up.

I think torrentprime hit the nail on the head. These Christianists cannot sell anything without shoving impending doom down the throats of their players. It's the only way they can sell their wiggets and therefore beg for money. They've seen that the single-cell brained minions of this country only see things through their warped glasses (shown by the successes of the Karl Rove machine).

By the way, my dog Kipper doesn't care about Christmas yet I'll continue to buy his dog food at PetSmart. They are really groveling at this point.