From: Lower Saxony Germany
You'll also have to garrision the Russian Production cities as Ivan tends to send a few Partisans to pay a visit. You don't want to lose supply or supply routes because of neglet.
Plus having to move fighting units back to recapture a town can be frustrating, esp when they are needed elsewhere.
I find it is nice to have base where new units can be formed and trained, fighting the partisans gives them a little xp and morale boost.
"It is not enough to expect a man to pay for the best, you must also give him what he pays for." Alfred Dunhill