Some Amish do have phones (just not in their homes). We just hired an Amish cabinet-maker, and he has called us twice from his shop.
He also made copies of our floor plan, on his diesel-powered copier.
Some technology is okay for them. They decide what's okay on an item-by-item basis.
Of course, you're right. The only problem I have with the Amish (read: why I could never be one, drat!) is that the women are way down the scale on the technology ladder. Electricity and phones in the barn (for business), but not in the house. This isn't a feminist rant, just an over simplification for those following along at home. (But I do love their clothes and quilts!)
One of the news stations had an Amish man on the air and his phone was also out in his shop. It IS bizarre that the ones that DON'T have phones will go to the neighbors and use theirs! They don't drive cars either, but will ride in them.