A toll-free phone number for your Shopify store gives you credibility and signals your customers you’re serious.

From the Krebs on Security blog

When people banking in the United States lose money because their payment card got skimmed at an ATM, gas pump or grocery store checkout terminal, they may face hassles or delays in recovering any lost funds, but they are almost always made whole by their financial institution. Yet, one class of Americans – those receiving food assistance benefits via state-issued prepaid debit cards – are particularly exposed to losses from skimming scams, and usually have little recourse to do anything about it.