Nice little article in the Herald historical series about the route choices made by the
GWR▸ and others through Oxfordshire and Berkshire:
Steventon Parkway Station"Next train on platform three is for London Paddington calling at Abingdon, Steventon, Reading and London Paddington."
Wallingford and Wantage might have been the 'natural' route for the main line west from a traffic perspective, but this would have been in direct competition with the existing turnpike and hence some local vested interests - irrespective of extra cost. In the end there was a road connection made with the turnpike at Didcot - the connection being the modern day Station Road to the former turnpike now Broadway.
Of course the Abingdon authorities soon realised their mistake but the eventual branch was too little and too late to arrest the start of its relative decline in importance in a Berkshire context, especially with respect to Reading.
In that way maybe Abingdon should be considered an Railway UnTown.