Actually, 0.02 just prevents massive amount of retraction on very small islands. For example, the Eiffel-tower has lots of tiny pillars, the 0.02 prevents that the filament is totally grind down on this print, without preventing a lot of retraction.
It will only retract on travel. However, during solid infills, it does travel from line to line, and do you want retractions there on every move?