Walmart, Cracker Barrel, and any other retail establishment don’t care one iota about your slides being out AS LONG AS you don’t block the roadway or take up double the spaces because of it.
I’m 64’ tip to tail with my motorhome and it’s toad. I’m going to take up the whatever # of spots (6-8) wether my slides are in or out. As long as I center up on that row of 6-8 spots, I can safely deploy my slides and it doesn’t intrude on the roadway or adjacent parking spots.
The only people who care are the people on internet groups and forums. No one else does.
Heck, the RV industry’s “Code of Conduct” which is blessed by Escapees, FMCA, Harvest Hosts, and others no longer specifically mentions slide out.
Run your slide out, just don’t take up extra space because of it.