Did they replace the sales and coupons with simply lower prices across the board? Because that would make it more attractive to buy there. If not, it's a price increase.
Yes, but the lower prices across the board were close to the average selling price before, not the best price you used to be able to get using a coupon for an item on sale. Therefore deal hunters no longer wanted to shop there. The price-insensitive folks still did, but they were the ones who used to pay full price and subsidize the deal hunters, and now they were getting a lower price than before. Thus it was a money losing strategy for the company.