We travel a lot out West and in the Great Plains. We never leave an awning out and some RV parks warn you about even extending any awning, day or night, even if you stay in the coach.
That said, I have seen awnings secured with anchors that are screwed in to the ground connected with ratchet straps. These were not the little screw in anchors used for a pet leash but were the type of anchors used for storage sheds, etc. If you are going to be at the site for a period of time, you may try the ground anchors if the park will allow them. I've never tried them and I am only saying that i have seen others using them.