New technology is upending everything in finance, from saving to trading to making payments.

This article is more than 2 years old.

July 2, 2015 This article is more than 2 years old.

This post has been updated.

Adding to their list of woes, Greeks can no longer use their PayPal accounts.

Limits on how much money Greeks can take out of banks put in place by their debt-stricken government as it negotiates with lenders have effectively crippled the online payment service, which relies on traditional banks and credit cards to transfer money.

According to a PayPal spokesman:

Due to the recent decisions of the Greek authorities on capital controls, funding of PayPal wallet from Greek bank accounts, as well as cross-border transactions, funded by any cards or bank accounts are currently not available. We aim to continue serving our valued customers in Greece in full, as we have for over a decade.

The economic crisis in Greece is obviously not emblematic of the greater global financial system. But the fact that PayPal’s business has ground to a halt there underscores how much it and other financial technology companies are reliant on the traditional institutions they were created to disrupt.

The truth is, there’s an old-fashioned bank at the heart of nearly every financial startup meant to put the old guard out of business.

Take online peer-to-peer lenders Lending Club and Prosper—neither of those companies actually holds loans on their balance sheets. Instead, it’s a Salt Lake City, Utah, bank called WebBank that issues most of those loans.

Likewise, Coinbase, the hot bitcoin wallet startup that lets people buy and store bitcoin, relies on Silicon Valley Bank in Santa Clara, California, to transfer bitcoin into US dollars and other fiat currencies. (Coinbase did opportunistically offer to waive transaction fees for all people buying bitcoin with Euros this week in an attempt to convince people of what they said were the benefits “of using a global currency that is not controlled by any particular country or company.”)

So while many of these startups present much-needed competition to the traditional financial system, PayPal’s shutdown in Greece reminds us how difficult it is to disintermediate banks from the flow of money.

Update (July 3, 2015): PayPal said some services, including receiving payments, remain available in Greece. However, funding PayPal wallets from Greek bank accounts, cross-border transactions, and certain payment attempts remain unavailable for now.

Quartz’s full coverage of Greece’s debt crisis can be found here.