You can go to Animate Online to see how the Free! merchandise section is decorated at each location of Animate in Japan, while the Japanese anime merchandise vendor is conducting a nationwide Free! store display contest. Each location shows uniqueness in the display, whether it's pushing a certain character or motif from the anime to make their presence known in the store. See some samples below!
Animate Sendai obviously is showing support for Rei.
Animate Shizuoka puts Haruka in the center since he won the popularity poll held at the location.
Animate Shibuya is also not ashamed to show their support for Rei. There are even red glasses frames for customers to use when taking photos with the life-size Rei standee.
While most of store displays are blue to go with water theme of the anime, Animate Yokohama is all red for Rin.
Animate Fukushima, above and many other locations supported Makoto, proving that he still gets a lot of votes from fans.
Animate Avanti Kyoto used the Butterfly swimmers. Many fans are looking forward to listen to their duet coming up in the future.