They do odd incremental pricing with a lot of things. I don't know that it's nefarious so much as it is nefarious. They know $14.99 is read by consumers as $15. $14.98 is a ratfucked $14.99. By the 0.80s we see it as $14.xx and it's perceptibly cheaper.
At a few of my retail jobs, the .xx system was shorthand for pricing types: .95-open box, .90-clearance, .97-manager's sale, whatever.
Doubles are just easy on the eyes, too.