[nikolay]

That's right. Many people obtain visas with the clear intention of changing their status, which is illegal, and so far, authorities have turned a blind eye to it. The typical progression is: people come on a J-1 visa, join a language cours to get an F1 visa, then drag it for as long as possible, graduate, which gives them the opportunity to work on campus for a short period of time, meanwhile, try to get married, or pay somebody to marry them fictitiously, or try to get an H-1B, which is almost impossible, or, in most cases, stay illegally, but now they have an SSN, and a driver's license, which nobody checks if they are authorized to work, so, there millions of people with SSNs and DLs, whose stay is completely illegal, and it's not too hard to identify them, but so far this illegal situation has been silently tolerated. Okay, if you knowingly allow violation of the law, then change the law so that people don't live with the sense of being unlawful residents! Oh, I forgot that illegal residents can have legal children and later on get green cards as parents of U.S. Citizens. All these scenarios are well known, including the abuse of L-1 visas by outsourcing companies, but, as I said, it's been tolerated.