Indian who travel in group/packs are the IT H1B1 visa guys. I know them, have been working them for the last 15 years. They almost never travel alone, always in groups, they have been trained and sent over here that way. I have come to know a lot about them over the 15 years I have been working with them.
Most of them are young single Indians, some are married but their family, wife and kids are in India, some are living with their families, but most are single Indians.
Indians are taking out IT jobs, now they are taking our whores too (LOL, man I was waiting to say that, as a joke)