I believe the SCOTUS ruled that malls are identical to city streets for purposes of peaceful protests.
This happened back in the '80s or early '90s.
The original case concerned a Planned Parenthood display and pamphlet operation in some big mall. The mall owners didn't want it and kicked PP out. PP went to court and argued that shopping malls were the functional equivalent of a town's main street, and that they were allowed therefore to peaceably assemble, petition for redress of grievances, etc.
They fought it all the way to the SCOTUS, and won.
This was before the "dead mall" phenomenon got started, and might actually have had something to do with it.