I lived in Russia and now live in Canada, and I would take Russian mobile market over Canadian any day. Dirt cheap, fierce competition between operators, over-abundant coverage, hidden fees are much less prevalent, there are contracts but pretty much everyone is on prepaid, buying new SIM card is a breeze.
I do not know if subsidized phones are forbidden, but much more likely the tradition of buying own phones is historical. Back in 90s owning a phone was a status symbol, there were no credit bureaus, no credit histories, inflation was rampant and ruble FX rate was very volatile. Everyone trusted only cold hard cash (preferably USD).
Later the country was swamped with lots and lots of cheap phones. So-called "grey" phones (euphemism for "smuggled") were brought in circumvention already lax or non-existent import regulations.
So I guess it is just not in the Russian tradition to sell subsidized phones.