Of all the known malware families that use DGAs to communicate with their C2, only very few use DGAs that generate non-random-looking domain names. For example, Suppobox generates domain names by randomly selecting a few words from a hard-coded word-list and concatenating them together. Rovnix does the same but uses publicly accessible copies of the U.S. Constitution rather than a hard-coded list.
The goal of this is pretty clear: to circumvent the algorithms used by security software that detect random-looking domain names. So this has me wondering: why don't more DGAs do this? For a malware designer, what are the possible downsides to using this strategy?