It’s not that they interview more rural than non-rural applicants (historically the ratio has been the same for interviews : offers in each category), it’s that the competition for rural interview slots is less fierce overall (on sheer numbers - not at all a comment on motivation), so there’s less drive to push the required UCAT through the roof.
A1 adds: We can see the numbers. According to Ms Sue, 260 rural out of total ~750 interview spots so 30% places 30% interview spots. This 260 is out of ~500 rural applicants vs 500 out of ~3,000 non-rural applicants.