Why aren't top consulting companies (i.e. McKinsey, BCG, Bain, Strategy&, ATK) visiting IIT Kharagpur during placements?

IIT Kharagpur is always open to consulting companies. However, the top consultants you mentioned don’t visit IIT Kharagpur usually because

• The recruiting in consulting companies is generally done by Partner level executives. These are extremely busy people who are paid hefty amounts for just one hour of counseling. 
• The consultants you mentioned have a small demand which is fulfilled by IIT Delhi or IIT Bombay wherever the main office is.
• Traveling to IIT Kharagpur requires 2-3 days and consultants are not that free
• The profile which goes to some of the local colleges may not be the same which comes to IITs.

But if you look from a positive aspect, although IIT Kharagpur was not visited by top consulting companies, it had more than 130 offers, which is the highest among IITs and packages offered, but at par with other IITs.