spotted in the wild...

[Laurence Horn]

...but not a new item for the bestiary; there's a nice treatment in
the eggcorn database.

In a student paper I just read, a reference is made to "deep-seeded racism".

As the discussion at
http://eggcorns.lascribe.net/index.php?s=seeded&submit=Search points
out, the eggcorn actually is more transparent in this case than the
original source "deep-seated" is, and of course the two are homonyms
in most varieties of U.S. English.

Larry