For music, the conservative equivalent is obviously country, especially since it's not just listened to in the South anymore.
For brands, I agree with Chick-fil-A as a proxy for the group that OP stated. Living in perhaps the epicenter of those types of voters, you would be amazed at how long the lines at Chick-fil-A get (they often back up traffic on nearby streets). Another cultural signifier I would add on the right is college football. There's a reason that Trump has taken such an aggressive stance in favor of college football being played. It might not get as much attention, but college football's fanbase is basically just as conservative as NASCAR's or golf's.
https://www.businessinsider.com/politics-sports-you-like-2013-3
Isn't Cracker Barrel a big culinary cultural signifier for White Southerners as well?
It can be, although it's more of a generic white Southerner cultural signifier than the more specific group that the OP noted. I'd even say that Cracker Barrel has more of a presence in the rural South than the suburban South (though we do have one near me). There was an interesting, albeit outdated, piece on the divide between places with a Cracker Barrel and a Whole Foods. I think there are now a lot more places with both of them though, so it's not quite as relevant.
Waffle House and Sonic are also examples, though they may just be partisan-leaning as a result of being regional.
I can buy Cracker Barrel vs. Whole Foods, but pretty much all of the other things discussed here are just too broadly popular with most Americans to automatically determine their political views. There's a surprising number of conservative rock stars and liberal country stars out there.
