I pay $6 extra every month for a dumb meter. When they rolled it out in my area, nothing was encrypted. You could join the zigbee network and see everything. It took them 4+ years to get called out on that and fix it.
As best I can tell the meters here are sampling in 30 second intervals, however the utility and commission are cagey about specifics. That seems a bit outside the scope of the stated purpose.