Many sea kayakers can't roll and never thought of learning, because
they don't paddle in waters that are likely to flip them to begin with.
As you know, it's not enough to learn, you have to practice every time
you go out. That's a lot of commitment to prevent a swim that might
happen once a year or less. People who want to go play in the surf
should know how to roll, although even there you could just swim in to
the beach if you needed to. Other than that, knowing how to do a deep
water re-entry is enough for most people.

Steve

Mary Malmros wrote:
For
reasons that are unclear to me, sea kayakers seem to regard the roll as
an incredibly advanced technique that you have to build up to for years
and years. In whitewater boating, working on a roll starts right away,
because there just aren't a lot of safe and pleasant places to swim in
whitewater ... Having a roll makes you a much safer boater, in any kind
of water.