Is it racial bias to have only Afrikaans and English lettering on the aisle signage?

I sometimes visit the Checkers in Northgate Mall, but the aisle signage that provides descriptions of the food items in that particular aisle either have English or Afrikaans lettering. I look forward to an explanation on why Afrikaans has been chosen out of the other SA languages. Has marketing research indicated that Afrikaans shoppers make up a significant percentage of funding or shoppers? I haven't done a rapid customer review or anything but the vast majority of shoppers and staff are black. If you have decided to place Afrikaans on the signage why haven't you put up the other languages?