The vast majority of the population are well within a $5 roundtrip to Aldi. I walk there.
Aldi turnover is @$2.5B/year and has 200+ stores - it is a mainstream retiailer.
Aldi is 15-30% cheaper than Coles or Woolworths not 1% as you imply.
Tesltra - credit card surcharge.
Qantas - credit card surcharge.
Most local councils - credit card surcharge.
Most internet providers - internet surcharge.
Harvey Norman - credit card surcharge.
Taxis - credit card surcharge.
The list is endless.
What's funny about that?
Use a credit card so that you can keep the cash in you mortgage offset account is a classic case of false economy. The banks love it because they make tens of millions of dollars from it.