Train stations aren’t always centrally located, especially in China where HSR stations can be as far away from city cores as airports. Japan also has some of that for smaller cities (eg Gifu vs Gifu-Hashima).
The French state railway company SNCF has a low-cost service high speed TGV service called Ouigo that also uses stations on the periphery of some cities (while regular TGV goes into central stations), just like low-cost airlines.
Sounds weird. The reason China and japan do is way is to keep the HSR track as straight and short as possible. Bringing a train into a city that isn’t an end point would probably slow it down a lot.
With Gifu-Hashima and other "rural" Shinkansen stations the reason is usually political. For example Gifu Prefecture would not allow the line to pass through the prefecture without a station being built. From Gifu city center it's actually faster to take a train to Nagoya and change to Shinkansen there, especially since every train stops at Nagoya and only a few at Gifu-Hashima.
In the case of Ouigo, I believe it’s in part because the station and track owner charges less to use peripheral stations than for central stations, and in part for price discrimination, so less price-sensitive business travelers and wealthier travelers aren’t tempted to go for the cheaper option.