Virat opened a inning and sometimes bats at 3, which means he had more balls to face in every match. On the other hand Parag bats at number 6 position and only gets to bat limited amount of balls so it's kinda obvious he's not going to outscore Kohli. Even Dinesh karthik who was in God Mode throughout this season scored less runs than Kohli.
Not the best comparison I have to say, and that is exactly because of the reason you mentioned.
Another obvious reason why most middle-order batsmen cannot score too many runs is that when they come out to bat they generally don't have the time to get settled. They have to swing their bat at almost everything. On the other hand, the top-order batsman certainly has some time to get settled. So, it is really easy to understand why Virat Kohli obviously has a better statistic in this comparison.