The Walking Dead brought viewers to several different places in the first half of Season 7, and while The Kingdom and The Sanctuary were largely similar to their comic book counterparts, the same couldn't quite be said for Oceanside, seen in the Tara-focused installment "Swear." The episode wasn't a hit with fans, but the all-female population made for some interesting speculation, and we'll thankfully get to learn more about it soon. According to showrunner Scott Gimple, it will connect with a character that definitely isn't Tara. In his words:
There's definitely unfinished business there. And the information that Oceanside --- and what it possesses --- would be a very big deal to Rick.
Aw, snap! Somebody inside of Oceanside, or perhaps everyone inside Oceanside, knows something that Rick doesn't know. (I tried to make that sound like singsong childish chiding, but it wasn't very good.) Though we didn't learn much beyond the general origin story from leader Nantania and the rest, it seems obvious to me that everything we did learn will play into how they're used in the future.
Before Oceanside was formed, the group's previous community became one of Negan's conquests, but it didn't take long to reach a breaking point. The survivors faced the Saviors head-on, but their valiant efforts were thwarted, and Negan's posse slaughtered all of the male residents, taking some of the consenting females back to the Sanctuary. Under the threat of death, the others hightailed it and set up shop in the Oceanside campground, hidden from outsiders' eyes. So it's pretty obvious how Rick would be assisted by coming into contact with them, since he's also going to begin planning a mutinous retaliation against Lucille's owner.
Rick won't be able to get any tips on how to defeat Negan, of course, but any information about one's enemy is good information to have. He, Michonne, Maggie, Sasha and the rest will be able to get an idea of how the Saviors strategize both their attacks and their defenses, in a way that will make more sense to them than it would have back before Negan showed his face. Daryl, Carl and Jesus could probably make a map on how to get back to the Sanctuary at this point, so Rick just needs a lot more intel on his foes themselves. That will surely make him smile.