I've seen canvas sukkot that have kiddush printed on the walls. Can you use the text to say kiddush?
Generally we can't benefit from the sukkah walls. For decorations, you can make a stipulation that they should be permitted (and this would probably take effect implicitly for a decoration with the text of kiddush, since that's the whole point of hanging it up), but this doesn't work for the walls (Rama 638:1).
And, while you might have argued that reading off of it is not using it, the Gemara (Shabbos 22b) directly compares Chanuka candles to the sukkah, and the main forbidden benefit from the Chanuka candles is to use their light.
Obviously the manufacturers believe it's allowed, but why?