While Star Wars: Episode VII - The Force Awakens was well received by many, there is still a subset of fans that aren't all in on the lore Disney is selling, and would like to see the expanded universe that came before it renewed.
The Give Us Legends group, headed by Matt Wilkins, sought out funding through Indiegogo to bring that request to the forefront, resulting in a billboard that can be found on Steiner and Lombard in San Francisco. You can see the banner above, which reads: "Dear Lucasfilm, Please continue THE ORIGINAL EXPANDED UNIVERSE — The epic story that existed from 1976-2014. Thank you."
The project raised a total of $4,784, with most of that going to the billboard. The remaining funds though went to buy Legends books for local libraries, which is a cool gesture.
The reason for the campaign and the billboard is to get the expanded Star Wars universe back in use in some form. When Disney took over the property, they relegated the existing comic books and novels to "Legends," noting that the future of Star Wars properties would be based only upon the films and Star Wars: The Clone Wars TV series. Everything else became "Legends," with aspects able to be pulled from at the will of the Star Wars Story Group and future storytellers.
It's fairly unclear what exactly the Give Us Legends group is seeking. Disney and Lucasfilm can't put the original expanded universe into canon now - The Force Awakens went in a drastically different direction from the EU, and new comics and novels set entirely in the new canon (plus Star Wars Rebels) have already been produced. Logistically, it doesn't make sense for any new content in what's basically an old alternate reality to be produced, when the purpose of changing it to "Legends" was to clean things up, not muck up the works further.