I agree with you Karthik, Its true, not just in US, when they travel out of india, they follow Law of the Land....
But, I have not seen the Expressway mentioned above, I live in China, here on Expressway, minimum speed of the Vehicle must be 60, max limit for Carriage is 80 Kms, Bus - 100 and cars - 120 Kms... but no Bikes, Auto, walking not allowed.
Totally protected roads, its very hard for people to stray into the Expressway (Xpresway).
In India, I think (Since last 3 years I have not been to Noida/Delhi), people walk on the road, cattle menance, given these problems, its safe to follow low speed limits...