No, there weren't many passengers at all.
While traveling in Karnataka Sampark Kranti Express from Pune to Yeswantpur, I have seen this train countless times (early arrival at Miraj). Always a negligible patronage from Kolhapur.
Also, this train was meant for connection of Karnataka Areas (SWR) to Bengaluru so nothing wrong in short terminating this train to maintain punctuality and Quota.
Works same way...
more... like Ajanta Express terminating at Manmad Junction for SCR areas, it's not meant to be extended to Nashik Road or Mumbai.