This is pretty common in south, where top heroes crossing collections of each other on day1..
This is called loyal fan following irrespective of genre(anyways south has one one genre that is action drama/comedy)..
Ex:mahesh,ntr,ram charan, chiranjeevi, pk.. They have always broken records of each others as the occupancy rate is near 100% and special shows...south audience have made an habit of watching films mandatory on day1..
But from 2nd day occupancy of south films falls in a huge percentage like 50-60%, where as in hindi it can jump by 5-10%even after a record day.
The most important factor is their language feeling.
Ap/nizam population is like 7-8cr.out of which 1-1.5cr people turnout to watch a blockbuster movie.. So 15-20 % of population is watching their regional movie, same in TN for vijay rajini ajith movies..
But if you take 60cr-70cr hindi speaking population, only 2cr ppl r watching for a blockbuster movie. That means 3-4% r watching.. Its a huge difference..
Though there are many hindi speaking states, yet they all dont feel the same for hindi language as telugu or tamilians feel..