That said, if Ukraine under Yanukovich was a puppet of Russia, you'd have expected them to give Ukraine better prices in the first place than some of the highest in Europe as well as neglecting to enforce repayment provisions strictly.
Here's what is apparently a map of Russia's gas prices from 2013 before Russo-Ukrainian relations soured, originally intended in the context of illustrating Russia's gas politics. Actual political partners Belarus and Armenia get the best prices, while potential partners in the West get moderate prices when compared to the less-influential East to ensure their continued reliance and undercut potential competitors. The worst-hit as far as prices are concerned are Poland and Macedonia, but Ukraine is not that far behind. Actually, Turkey doesn't surprise me quite as much, but seeing Bulgaria's high prices surprises me a little; I suspect it was part of the South Stream politics where they were promised lower prices once the South Stream went online. I suspect most of the tolerance for Ukraine's "derping out on gas payments," as Sergarr eloquently and accurately put it, was mostly just an attempt to refinance in order to get some of their money back, rather than an attempt at political puppetry. Turn off the gasworks completely, and they not only have to write those payments off completely, but also have to worry about the Ukrainians siphoning off from the major pipelines that run through their country (accusations and examples of which have been flying around for at least
six EDIT: twenty years). Indeed, one of the reasons why Ukraine's prices rose significantly after that data above was collected was because one of the major discounts for timely repayment of those debts was cancelled, shortly after Russia also cancelled the discounts that were part of the deals made regarding Sevastopol (by virtue of seizing control of the port, city, and entire peninsula directly, but let's not quibble over details).