If this grill has been built from scratch, why even have the leg sockets? You can see this is mounted on a cart with the wheels in the background.
Probably for the same reason every Performer since 1990 has had leg sockets, just take a kettle off the line, add support tabs for the table to it and drill holes for the lid bale. My '92 even has a front handle loop, unseen unless removed from the table/looked at from below.
Then again, if this is a unique, double-wall bowl, then the sockets were added only for the ash catcher.
Wonder if they'll offer any colors other than blaik.