For years, I took the "moral" high ground and never phoned for discounts, as I thought it was unethical, while all all along reading posts here about people getting great discounts.
One day I thought to myself, what, as with most business', VM are overcharging for their products and the discounted price is closer to the true price? I then phoned up retentions and never looked back.
These days I think the discounted prices are overcharged too!