A possible explanation for that is the difference between different currencies is the demand in that particular place. Let's say that in ARS, the increase of that price was probably because of the loss of confidence in their fiat currency [1]. Some people might have been looking for another way or another asset to save their money. Compared to other countries, most people are just going out of their way and not giving much volume towards Bitcoin transactions, hence the lower price. You could arbitrage that if you want to profit from that discrepancy.

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[1] - https://news.bitcoin.com/1-4m-in-bitcoin-transactions-new-high-for-argentina-as-confidence-in-the-peso-tanks/