Disrespect for customers

My husband and I went to buy a bathroom extractor fan, we had decided on the one we wanted but only to notice that the one on display was different in style to the one we were going to purchase. Preferring the displayed one, we requested the same style. The salesman told us it was a very old design(probably 3 years old), nevertheless we did want the displayed one and inquired about the cost.The message was sent from the manager on duty that it was a 10% discount. We then asked to see the manager because, whilst we wanted the displayed one, it was 3 years old and was discounted, so in fairness, 10% off was unfair.We were met with rudest woman we had ever dealt with at Builder's, she thought that we will school us in SA's Customer Law, telling us that in SA there's no such thing as guarantees or warranties, also that we are the only people complaining(we weren't complaining, just stating the facts!), and how she was not prepared to lose money because we were complaining when other customers just buy the one on sale.We were disgusted by her behaviour and asked her to please leave so we can shop within her insults. Utterly disappointed, as we are very regular customers at this Builders