For one, the picture quality is gorgeous. It’s a dramatic improvement over common LCD displays in contrast, color saturation, and viewing angles (a factor all too important in hotel lobbies or other areas where the display will be viewed from all over a room).
Two, since there is no backlight required, OLED screens are extremely light and thin (less than a centimeter deep) — meaning installers have much more flexibility about where they can be placed. They can even curve and/or display content on both sides of the display.