They probably convince themselves it'll dissipate by the time they get there. In terms of range for the largest cohort headed south from the Bay Area, KC is the sweet spot, with Harris Ranch and Buttonwillow/Bakersfield on either side.
With so many SCs it's less likely and not more so, that people will carefully plan for certain SCs being heavily utilized. I didn't have a problem at any SC last weekend, but then I specifically avoided the coming weekend.
Given a near full charge starting from Bay Area, most cars will stop at Kettleman southbound. Tesla appears to recognize this, given the permitting of a second SC in Kettleman City:
Supercharger - Kettleman City 2, CA (permit found)