Refuse R4000 due to R500 eye test

Was at Specsavers Menlyn where Wilhemina assisted me I requested the special, where I would like to use the R1500 for a 2nd pair of glasses and I would like her to use my script seeing that I've used their services before. Firstly she had no clue with regards to the special but when I mentioned that I wanted to use my old script and don't have time for an eye test. Her story change to I can't use my old script seeing that it's 2 years old and if I want to make use of the special my eye test must be less than 6 months old. I declined. And it baffles me how your staff is willing to loose out on about R4000 in total for my glasses due to the fact that I dknt want an eye test of R500. Can yiu please explain to me where's the logic in that.