Do only toppers get hostels in IIT Indore?

No, everyone gets a hostel accommodation at IIT Indore and it's not only the toppers who get hostels here. However, there is a kind of distinction in the facilities offered to them. The normal students get facilities such as

• 5 BHK flats to accommodate 5 students meaning single occupancy rooms 
• Large spacious rooms with Cot, Almirah, Study Table, Chair
• Refrigerator
• Telephone
• RO Drinking Water
• Hot Water
• Sofa Set
• Discussion Table
• Wi-Fi Connection & LAN port
• Individual Attached Bathroom

Whereas students who have got AIR<=300 get the following facilities

• 1 BHK flats to every student that are fully furnished studio apartment
• Large spacious bedroom with Bed, Almirah, Study Table, Chair
• Hall with LED HD TV
• Refrigerator
• Telephone
• RO Drinking Water
• Hot Water
• Sofa Set
• Wi-Fi Connection & LAN port
• Individually attached bathroom
• Dining platform

Although there aren't any major differences, toppers certainly get more privacy than normal students.