Current draw vs # of radios active? (XBee 2.4GHz S1 & S2C)

We’re optimizing our firmware in a product that used XBee 2.4GHz S1 radios, and will be switching to S2C. We use DigiMesh protocol and the devices are setup as non-routing (end devices).

Some people in the company think that the current consumption (these are powered by a single AAA battery) is higher when there are more units powered on. In other words, if you test battery life for a single unit on versus 10 units on, the battery life will be longer for the single unit and the 10 units will have a much shorter battery life.

Is this likely? I haven’t tested this out yet, but I assumed since they are end devices there is no handshaking (or similar) going on that might account for this.

Thanks for any ideas that might explain (or discredit) this idea.

Tom