There is a Devon Day Ranger (i.e. rover) ticket at £10 adult (£6.60 oap) so there is no point in trying to sell "ordinary" off-peak day returns at any higher price. So the day return is priced accordingly and more cheaply. The ranger would have been fbb's choice if he had longer time in Plymouth, possibly for a picturesque ride to Gunnislake and back.
Ranger information was not apparent at Stagecoach-land's Axminster; but then the ticket is a F*rst Gr**t W*st*rn product. Axminster is (a) in Devon (just) and (b) part of the ticket's validity. On enquiry, the young gell at the ticket window went to her cupboard of secret things and found a copy of the F*rst Gr**t W*st*rn booklet.
But fbb found the off-peak day return fare on-line, pegged to below the ranger price, and only later was able to read about the ranger from the little booklet prised out of Axminster ticket office, but not on display.
We're on our way to Torpoint.
They are heartbroken.