Pretty much works as you imagine. Drop dice in the top, they roll through the chute and land in the bottom. 

The idea was to give a better place for rolling the dice that everyone around the table can reach.  

There are two versions of the dice tower. V1 has been printed but does not leave much room to collect the dice and more thought was needed to design it for better printing (too many large unsupported spans). 

V2 is the latest iteration, yet to be printed (still figuring out how to design for printing).