Lifting strakes will have more glass in them than a chine, simply due to how they are built. But I agree with others that it most likely is not structural. Rap on it real good with your knuckles and compare to other areas. I suspect you won't notice a difference in the sound.
Gelcoat is actually quite brittle and can crack easily with a slight impact - and what may have started out as a small spider crack can get bigger. Also, spider cracks can, and do, continue to spread. The fix is relatively straight forward but it does take some time. An important piece is to drill a small, shallow hole at the end of each crack to stop it from spreading.
Another factor is that if the gel was put on too thick at the time of the build, it actually makes it more prone to cracking.