But is it being figurative? Is it being literal? I suppose in a very real sense, it's both. The Living God in His Foresight, has known these sins would take place (and when, and how often, and by whom, etc) throughout all Eternity. Consequently, He has also known they would Offend his Infinite Justice. And in that sense, that knowledge in the mind of the Sublime is the actual "crying out." Because these deeds so offend against His Will that they are like the proverbial fingernails on chalkboard. Although He never fails to take note of anything, these things He takes note of in a very special way.
I hadn't caught the "the wages...are crying aloud" construct before. It reminds me of the magic harp Jack (of beanstalk fame) steals from the giant, which called out to its master in a way that people don't ordinarily expect things they're stealing to do.
In fact, the treasure the rich store up for the last days plays quite an active role in this passage. Verse 3 says:
...your gold and silver have corroded, and that corrosion will be a testimony against you; it will devour your flesh like a fire.
The hoarded wealth not only cries aloud, but after it corrodes, it acts as a witness for the prosecution -- and, in a particularly ghoulish image, it goes on to corrode the flesh of the rich!
Excess wealth is some nasty stuff. What sane person would keep it in his house?