hooooooly shit i never even thought about it ... but bitcoin could be used to pay illegal immigrants off book now that you pointed it out ... nevermind the obvious that it's used by cyber criminals drug traffickers and sex criminals , everyone knows that ... is there no crime bitcoin doesn't make easier to commit through obfuscation of the money source ?
How is it easier than just using cash? Illegal immigrants don't always have a steady phone or one with internet, and all the crimes are just as easy with cash.
Provided that the recipient has some way of receiving the bitcoins, then I would think it's easier than using cash but it also brings a lot of downsides as you rightly point out. Cash can still leave a trail which conventional tools used by the government can easily uncover. And when it comes to cybercrimes which is what the OP is about, using cash isn't really a realistic option.
For most people, in order to get cash in the first place, you need to get it from a bank or a bank's ATM, or collect it by doing business activities. This isn't a huge problem if you're dealing with hundreds or a few thousand dollars worth of cash but it becomes unrealistic when you're dealing with tens or hundreds of thousands of dollars. More significantly, the IRS has been known to clamp down on businesses that deal mostly in cash and signs that the business is avoiding taxes by using cash to pay its employees can still be discovered during an audit.
Finally, the IRS also encourages people to report employers who try to avoid taxes by awarding whoever reports it with a small percentage of the seized funds:
The IRS Whistleblower Office pays money to people who blow the whistle on persons who fail to pay the tax that they owe. If the IRS uses information provided by the whistleblower, it can award the whistleblower up to 30 percent of the additional tax, penalty and other amounts it collects.
Source:
http://www.irs.gov/uac/Whistleblower-Informant-AwardWith cash, this would be easy for the IRS (and by extension, other branches of the government) to achieve. With a typical Bitcoin wallet, this would be difficult. Even if you had terrible security practices in place and your transactions gave away your identity, it would still be highly difficult to track down and prosecute since conventional tools and techniques that the FBI and IRS use to detect illicit fiat transfers obviously don't work with Bitcoin. And with a properly secured and encrypted Bitcoin wallet, this sort of stuff would be impossible.