There are many simple hooks and they have many advantages:

Injury less the fish than with triples - Perfect for catch'n release ! - A simple grip less in congested environments (algae, stones, etc.) - A single tip pierces better the hard cartilages (principle of assist hook for jigs) - Painting lures less damaged than with triples - If you happen to break on a fish, it will be more likely to live with a simple in the mouth with a triple.

Specialist lures recommend simple hooks in all fishing practice from exotic to rockfishing!