I posted a photo some years ago of the jack tubes with the rocker cut away. They are much more durable than you might imagine looking at a rotten rocker panel. The rocker has no structural bearing on the jack tubes themselves. However, dont take my work for it-- use jackstands by all means.

I too have seen unscrupulous sellers plaster right over the jack tubes. What fun when you show them the jack and ask where it should be inserted!