Conjure Tasty Treat produces the item entity at the -x/-y/-z corner of the block you supply rather than the exact position in the vector

[beholderface]

I was trying to tell it to conjure them in the center of the block space that the one closest to my cursor is in, but they all spawned in the corner. The vector in chat is from a Reveal placed just before the conjure spell in the wisp's hex.