IIIT-H has just two branches: CSE and ECE, the two branches with highest average package in the world. IIT’s on the other hand have hundreds of branches including metallurgy, production engineering etc. where the packages aren’t too high.
So, comparing the average package of IIIT-H with that of IIT is totally absurd. On the other hand, if you compare the average package of IIIT-H CSE with that of IIT CSE, you will find that IIT’s are way ahead.