You're seeing farther into this than most.
There has always been the mutual expectation that foreign DIPLOMATS will get a free ride and live the good life in the US and most elsewhere.
This is optics, only Russian diplomats do this? More likely this is a sign of non cooperation on the Obama regime, and a very stupid one at that.
This could go very wrong as US citizens with government connections go to bed in foreign nations all over the world, and wake up in Russian jails charged with serious crimes.
It is a big no-no to make these stories public in terms of civilized diplomacy. It is something you can await from Zimbabwean or North Korean officials. FBI should have informed the Russian Foreign Ministry and make Medicaid sent them a bill. It is exactly how Russia, Germany, UK or any other civilized country does if any US diplomats are invovled in such a things abroad (and it happends much more often than one may think).
I don’t think any American businessmen will suffer as a result. It is simply not classy and Russians won’t act this way but you can see some incompetent CIA operators working in Russia exposed in the most humiliating way soon as a counterreaction.