There is a traditional conflict in Christianity about wealth, and the use of wealth, whether it was better to live in poverty or to glorify God through beautiful (and costly) works. Think back to the middle ages, the difference between the monastic and priestly orders. Later, there was acquisition of wealth by each, the seizure of the monasteries in England, the destruction of the Knights Templar, the Protestant reformation, etc. The televangelists of the 80's and the modern megachurches certainly take in an awful lot of money.
As far as Rev. Billy goes, I don't really understand him. He doesn't really mean NO shopping does he? I'm guessing he buys white suits and hair gel at the very least. And a computer. Trade in general helps everyone have better, healthier, less wasteful lives. You can raise seafood in Oklahoma and grow tomatoes in Alaska if you want to, but it consumes a lot fewer resources to do things the other way around and trade the surplus.
