Well, I'm not sure what a music's "feel" is, honestly.
And the lyrics aren't any more punk than a tame Rage Against the Machine or something. The Crass lyrical comparison is good I guess, but that doesn't make Paranoid a punk album. If punk is an attitude, they're kinda punk sure. But so are lots of non-punk bands. Hell, Wolf Eyes is sorta punk.
And then there's great lyrics like this:
"I LOVE YOU!!!!!!
WHEN I FIRST MET YOU!