They can put it on their resume but with out their name there's no proof they did any work. You can now put it on your resume and pretend you did it because no one is named.
It's done out of fear someone else might know who did their work and someone else might hire them, so by not naming them they weaken the employees chance of getting work elsewhere.
Stop defending this shit, this is a company dehumanizing their employees and your taking the companies side?