This is so cool, really shows how much detail they put into this game's lore. I especially find it cool they have logos of the companies that are more prominent on specific stages, like real world sponsorships. Kinda helps explain how inkopolis has the money to pay for turf wars. (Especially when the inklings tend to spend a lot of the money they earn on a back alley druggie)
Reminds me, looking on the trucks that arrive the day before a splatfest, they have logos from the different clothing brands all over them. I thought it was just an Easter egg, but it might be sponsors for the splatfest! Or maybe I'm looking too deep into this.