Many of our local cafes and eating places charge a Sunday and public holiday surcharge, very rare that any place doesn't. It has been that way for many years.
My other half always ask the servers if they get the penalty rates, if they say yes, we stay.
I was at the local Vietnamese bread shop yesterday with granddaughter, we bought a couple of things, (which included a cookie with smarties on top) $11, no CC now. I only had a $10 note in my phone case. I looked at the lady and she said you owe me $1 next time.