Toy Empire Online

Bought a voucher from Jump On It. Searched the online store prior to buying to see what toys are available. However seems overnight this online store increased several prices from $69.99 to $99.99, a whopping $30 price rise just 'after' their online offer ended. There goes the discount we all think we are getting! The walker they currently have is $25 at BIG W, they want $59.99. Overpriced and lack of stock availability and range considering the amount of vouchers they sold online (over 600). Unhappy about price rises overnight, or I wonder if they reduced prices online first to entice people to buy vouchers? Either way, it's not an ethical and honest way to do business as far as I'm concerned.