I have a hard time with the some-is-better than none argument because the notion, “At least they’re better off than the homeless” encourages complacency when there’s much room for improvement.
In your donut shop example, I’d say that if you’re determined to run the business despite being unable to pay a just/living wage to your employees, it should gnaw at your conscience to think that those who work hard for you are unable to make ends meet on what you pay them. This should be addressed through both prayer and advocacy. The latter would entail making your community more local business-friendly. There are some inane costs and regulations that burden small business owners and could instead be shifted toward better payment of their employees.
I realize that this thread is long, but I’ve actually addressed both the large corporations and small businesses, the latter of which I stated would improve if large corporations took on their share of taxes and health insurance were separated from employers.
Finally, keep in mind that higher wages will help business and the economy at large; people who have more money can spend more money.