Moorfields is the most likely place to change trains on this journey. At Moorfields it's probably a 10 minute round trip from the platforms to buy a ticket. As you aren't supposed to miss a connection, the fact that there are 8-12 tph makes the OPs case stronger as going to the ticket office means they certain to miss 1 or 2 trains.
Would minimum connection times (MCT) come into consideration though in regards to "missing 1 or 2 trains"? The MCT at Moorfields is 10 minutes.
Trains from Bebington arrive at Moorfields at XX11, XX18, XX26, XX41, XX48, XX56.
Trains to Sandhills from Moorfields depart at XX04, XX07, XX11, XX19, XX26, XX34, XX37, XX41, XX49, XX52, XX56.
Arguably the connections from a Bebington service to a Sandhills service don't meet the MCT anyway (i.e. arriving on the XX11, your next valid service meeting with the MCT would be the XX26, and not the XX19 even though you could probably get to the platform in time).
But there must be signage on the platform indicating where to go for tickets (Google Maps suggests that there is), and that goes against not knowing where the ticket office is.
There is signage above the exit staircase at Sandhills, but as
@Bletchleyite has pointed out, it is incredibly easy to miss in a football crowd, as it is well above head height. It also could be considered mildly confusing as it has straight on arrows, which could be interpreted as going down the stairs to someone who is not familiar with the station.