PPPoE subinterface traffic counted twice

We’re seeing this interface report about 200Mb of Tx traffic, while we estimate it to be transporting about 100Mb of PPPoE traffic only.

We have come to the conclusion that it is counting the traffic twice (once for the physical interface, and again for the sum of the PPPoE subinterfaces).

This behaviour didn’t happen in version 5.26 for example. Is this correct?