BraCuru, I can see why it is not really "seen".
1. Those living for riding waves (like I do), will of course do it in waves too on a foil, but when we ride waves often, at the same time, there is not anything that looks "exciting" in any way with a foilboard, compared to waveriding on a waveboard.
2. Most wavespots have conditions with rocks or reefbreaks and difficult to get out/in, besides breaking and losing your foil, so often NOT suitable for foilboards whatsoever.
3. Those who almost ONLY ride foils, will do it yes (and some of the french guys do it !), but as it is in such early stages, it does not look good seen from the spectators view - so even those doing it, will hesitate to display a video they know looks boring and pointless to 99,9% of the viewers
(PS: I think everybody should DEFINITELY continue to display anything they got in waves, as this is a specific foil forum only in here, so it makes sense - and some are gonna be frontiers)
4. If you ride "both" and have no preferences, one over another, it is very very difficult to see any advantage whatsoever, with a foilboard compared to a waveboard, in waves.
And you can see loads of downsides and difficulties and missing aspects, when on the foil
5. Most foilboard riders are still "learning" more basic things, like tacking while foiling and other really difficult moves - so there are lots of awesome things to do for years, and you dont "seek" the wave aspect because of boredom, right away
Thats my take on why it is hardly happening at all.
I dont say it aint gonna happen - as everything is possible when new ground, and some day some might find the "holy grail" to what works and how to use it to an advantage instead - with a foilboard in waves.