Zebra Books used some ludicrous and cheesy art for most of their paperback originals they published in the 1980s and beyond, but the horror titles they put out in the 1970s had much more vintage-styled covers. Definitely some quality work for their reprints of pulp kings like Robert E. Howard, Frank Belknap Long, and Robert Bloch. Gaze upon the mighty art of Jeff Jones above, in the 1976 edition of Pigeons from Hell. Okay, sure, that's not even close to what goes on in Howard's seminal 1938 horror story, but how can you not be charmed at the evocative mystery of old-style dinosaurs cavorting in the surf?
Night Fear (1979) from Long boasts some kind of Elephant Man that I think is supposed to evoke the Cthulhu sculpture from Lovecraft. Art by Clyde Caldwell.
Also in '79, Zebra reprinted some of Bram Stoker's other works, The Lair of the White Worm (1911), Jewel of the Seven Stars (1903), and Dracula's Guest (1914). I'm digging 'em all!
But then as the decade turned, Zebra suddenly switched to the endless procession of dancing skeletons and wide-eyed innocents to sell their books, and a brand-new horror cliche was born. Most just look like Halloween decorations today, and have about as much atmosphere. Consider Wild Violets by Ruth Baker Field: the first cover is from 1980; the second, from '86.
See what they did there? Another example is Leslie Whitten's The Alchemist, published by Avon in 1974 with a pretty cool, well-painted cover that's part of a set with his Progeny of the Adder; 12 years later... ooh, a skeleton and a pumpkin! And Leslie is changed to "Les," because, of course, men won't read books by women... even though Leslie Whitten is a man.
I wonder though what the impetus was for this change: were readers actually getting less demanding? More likely, the horror paperback boom was happening so fast the publishers had to use cheaper, and thus crappier, art, as well as those foil-stamped titles, to stand out from other books on the drugstore racks. So basically, from the otherworldly eeriness of Jeff Jones's art to the utterly tacky, silly, and lamentable covers like the ones below...