The show is a homoesxual allegory

Is my reading. A few ideas:

Becoming "a zombie" is not a choice the person makes. At a certain point it just happens to them, similarly to how at a certain point, someone just realises they are gay. The MP says in the first episode the rotters didn't "choose" to attack anyone.

A big part of the show is family acceptance. Ren's sister refuses to believe he is the same person at first, and the act of "coming home" from treatment was akin to the act of "coming out". Ren's parents awkwardly and uncomfortably accept him.

There is a strong line of bigotry in the town and a refusal to accept the zombies. The town is portrayed as a bit hickish, so I feel this works with the gay-bashing backwoods town archetype.

Ric's dad is fiercely anti-rotter, until he finds out his son is one. This happens frequently with more conservative families.

Ric "became undead" and then came home from the military. It's flakey, but one could draw some don't ask/don't tell similes there.

Ric and Ren just seem to have that relationship. Ren states his world was empty without Ric, that he kept the idea of "them" alive when Ric left etc. He even said they "fooled around" (though that could be read as them just goofing off or hanging out).

There are also a bunch of little things - the one guy saying Ren would have fit in at a girls school, etc. During the first episode, a few specific choices of language stuck out to me, but I can't remember them all. I don't know if the schow is TOTALLY about homosexuality, but in the case of Ren, it seems to be a metaphor. What do you guys think?