Think logically about it, of course this will happen. The labor market for office jobs is completely broken to the point that many or most companies have no control of whether their employees are doing anything productive. Corporate work is mostly a charade and a wealth distribution scheme, also when it comes to software engineering - as evident by the many single individuals shipping software with better quality than huge corps employing thousands.

The hope of these fake candidates is that they can sneak in and get a few good paychecks from a corrupt and disorderly employer. And it costs then almost nothing to try.