There are 6 sports I can think of that would readily adapt to these river waves.  Surfing, river surfing, wake surfing, freestyle kayak, skateboarding, and snowboarding.  I have done most of these sports and the similarities allow for quick adoption of the others as long as you are proficient at one of them.  These are all balance sports and people like to watch athletes.

 

Everyone wants that perfect shaped wave and once they have it, they want it bigger. 

 

Surfing

Just about everyone has heard about Surfing.  Started in Hawaii and now spread world wide.  Waves are fickle and waves that are near civilization or easy to get to are usually well predicted and crowded. 

PipelineCloud BreakJ-BayMalibu, Average Florida day,

Trestles,

Wake Surfing

Requires a big heavy boat with a big wake.  Any flat relatively calm water can work for this.  Its just like surfing a small fast wave.  Boats are now being specialty built for this sport.  As you can see by the sponsoring, there is big money at hand.    

Ashley KidShane Blanton$135K Wake BoatYacht Surfing,   Best Flow Rider

River Surfing

Lesser known because the waves are less common and less people ride them.  But this is starting to change.  Downtown Munich has the Eisbach.  Home of the kick flip.  People surf it year round and Red Bull hosts events there.    

EIsbach:  Fus Jam 2016Fus Jam 2011Fus Jam 2009

Bend OregonJackson HoleWaimea bay,  

Freestyle Kayak

Similar to river surfing, but done in a specialized Kayak.  It is a competitive sport and I know very little about it aside from they want better waves too.  We all want better waves.

Kayak CompetitionUgandaKayaking extremes, Team USA TrainingPyranha boat PromoOcean Waves,

 

Location

When comparing all of the balance sports they seam to be location driven.  If you live at the beach surf is more readily available.  If you live in the city grabbing a skateboard is quicker than driving to the beach.  If you live in the mountains you might be a skier or a snow boarder.  In each of these cases the sport that is convenient or close to home is the sport the athlete adapts to.  I grew up on a lake and an hour from the beach.  Waterskiing and surfing are what I learned when young.  If river surfing is close to home people will adapt to it. 

The following communities (and hundreds more) have river waves and people come.  

Fibark,  Munich Eisbach, Bratislava, Jackson Hole, Boise Idaho, Big Sur, Glenwood Springs,  hundreds more.