That's not the same thing as people who know they want to buy X brand online but don't know what size, and go to a store for the sole purpose of determining which size to get.
But ... if the person wanted to buy X brand, and found X brand for a good price online, and went to a shop with the idea that he/she would determine what size to get ... and once in the shop discovered that the shop was selling X brand for the same price as online or less ... that person would likely buy the shorts there and then from the shop. The intent is to get the best deal.