Because the swell was gentle, when the outgoing wave hit the incoming swell, it created some interesting wave patterns. [In all of these pictures, the ocean is to the left side of the photo and the beach is to the right.)
I'm not sure if you can tell what's happening in the picture above, but this is what it looked like when the two waves came together (one moving towards the beach and the other traveling away from the beach) — a tall "swoosh" rising vertically, but not curling much.
Here's another example — a more tumultuous one (and generally more typical), but note the upward "swoosh" at the far end of the wave.
And one more for the record: