Did anyone else misunderstand Wiggle's recent sale and voucher offer.

It was an offer to buy something between 24 dec and 17 jan to get vouchers totalling £90 if you spend a certain amount.

I thought you had to spend a certain amount to get the vouchers initially, so blew £200 thinking I'd get the vouchers to spend on whatever I wanted.

Not sure how clear I've made that. Anyone know what I mean and make the same mistake?