Too true. Only a few ever get that honor.
Back in about ch. 25 or so (when King rejoins the sins), Ban is drunk and asleep and he appears to be speaking to Elaine about how he planted it, with 'it' not being known at the time. Roughly 80 chapters later, we find out he planted a seed and restored the Fairy forest.
Back before even that (around ch. 2 or 3 when Meliodas and Elizabeth were in Vanya), the patrons of the bar spoke of Camelot and how the new king was really young. Then 50+ chapters later, Arthur makes his appearance as Camelot's young new king.
Then there's the book Dreyfus was reading back around ch. 30 or so and we completely overlooked that, of course. And there was also Hendricksen's commentary to Jericho and Twigo back when he offered them demon blood. Surely, in hindsight, it would make sense for him, the researcher of demons, to have partaken in the blood too.