I read "they" in the phrase "... but they are also reportedly paying their telco providers to send the data." to mean Google were paying, so it wouldn't appear in the metered usage for which the end user is billed. This makes sense, as it seems the data apparently can be transferred when "... they do not have a Sim card or apps installed."

What would bother me, though, is if they were purposefully not exposing that data transfer in the data metering on the device. That seems shady.