Interesting that there are no Day Return fares for this journey, either Standard or Off Peak.
Another as you say classic example of our crazy fares system.
Pewsey has for many years been a "London facing" station. 50 years ago there were but 2 departures each way per day - at 07:56 and 09:00 to London (arriving 09:47 with a change at Reading, and 10:25), with return trains from London at 17:03 and 18:30 - both through trains, arriving Pewsey at 19:04 and 19:54.
Even today, you'll find that if you want to travel west before midday, you have a choice of the 08:09 and ... err ... no choice, whereas for London you have trains at 06:18, 06:33, 07:20, 08:10 and 10:19, with a "chicken and egg" suggestion that they're that poor because not many people use them where (talking to people) suggests significant interest in living in Pewsey Vale and commenting to Bath or Bristol. If only the one morning journey weren't nearly half an hour longer than it needs to be - longish wait for a connection at Westbury onto a s-l-o-w onward service arriving well after 9 a.m. and would only work for flexible employment, and rubbed in for people travelling home late by a return service that's 24 minutes faster.
Interestingly, there are day return fares from Pewsey to Bristol Temple Meads - £18.10 which looks like a snip against the £32.60 from Melksham. An off peak return from Pewsey to Salisbury is £19.50 - at peak times it's £69.20 which you would be asked to pay if you were commuting from Salisbury into Pewsey, but not if you were commuting Pewsey to Salisbury.
The Pewsey [Vale] Rail Users Group that we're looking to help seed may well wish to take up some of these fare issues with
GWR▸ and we can make introductions, and indeed the 4 hour gap in the morning is already on the agenda with movements being made towards narrowing it. And I can see other commuter flows growing as services are updated with new trains and different running times.