If there are ticket machines at both stations there is no excuse for not paying in one direction.
Please read my post more carefully. Perhaps I could have worded it more clearly.
It's a toss-up whether my wife and I get seen going from Stapleton Road to Redland or Clifton Down, in fact I'd say mostly we go free, but feel we have to pay coming back as there are ticket machines at those two stations.
'Those two stations' refers to the immediately preceding named stations, Redland and Clifton Down, either of which we might travel to. These have ticket machines.
Stapleton Road, our local station, has none, although it has GWR smart card readers.
We don't have these cards, and we don't use phone apps or e-tickets.
Stapleton Road is not a Penalty Fare station, although the others we may go to, and return from, mostly are.
We always board the outward train with cash and debit cards ready to pay. We 'feel',
because it is the law, that we have to buy a ticket before boarding a train to return to Stapleton Road.
Sometimes, more often than not (much more than 50% of the time), nobody selling/checking tickets has appeared through the train by the time we get to our destination station. I don't mean they are working their way along and haven't got to us. I mean nobody has emerged from a cab. Once I approached the GWR person despatching the train at Redland, and she just waved me away.
I hope that is clearer.
I assure you that my wife and I are very far from being 'fare dodgers'.
What do you suggest we do in such a situation?
Extract from GWR Penalty Fare map. Solid green circles are Penalty Fare stations which, as far as I know, have ticket machines.

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