Kent
You are right that most any cat will take a beating with a summer thunderstorm and should be tied down when left with the mast up. My boat was tied down next to an i20 and the i20 got thrown 50ft by a thunderstorm. Both boats suffered broken masts.

I use wood buried a couple feet to tie my boat down on beach.

If the boat is on gravel or on grass I have two 1 1/2 thick tent poles, the ones that the tent rental places use. They have old ones that they will sell you cheap. You can pound the tent poles into a parking lot or a gravel lot if you had to.

Any screw will be hard to get into rocky soil. Tent poles are way easier to pound into the ground.

Bill