I don’t know if any SuperGold card holders follow me but this discount is even better at Noel Leeming (where I used to work). There it is cost + 10%, which can be huge, particularly on accessories and small appliances, the latter of which sometimes have 50% markup in the retail price!

https://www.rnz.co.nz/news/business/1213112/supergold-card-holders-missing-out-on-discounts