My understanding of the term "Glatt kosher" which I heard from 3 different mashgichim (kashrut supervisors)
The term "glatt" means "smooth" and applies only to beef and lamb. (I would assume that it applies to goat, venison and bison, but those items are less commonly obtainable in the U.S.)
It does not apply to poultry (chicken, turkey, duck). It does not apply to produce, spices, or dairy.
Given the last paragraph, several years ago, I saw a bottle of Pereg Oregano that had both a "glatt kosher" marking as well as saying "parve" - a contradiction, obviously. A produce store in my neighborhood is called "Glatt Farm", when they sell only produce.
One of the mashgichim explained that the term "glatt kosher" somehow came to mean "strictly kosher". In other words, it has been used as a marketing tool.
Glatt kosher products tend to cost more than regular kosher products. I am also aware of many people who don't understand the correct vs. "marketing" usage of this term, who go out of their way to find a store that sells only glatt kosher chickens and glatt kosher produce. This seems like a waste of money and time.
My question, isn't usage of this term a rather clear case of "Genivat Da'at" - taking advantage of someone's ignorance and misleading them.
I esp. question the usage of "glatt" on produce that's whole and uncut and it was farmed outside Israel, and does not need to be inspected for insects. What on earth (pun intended, here) could possibly make such produce more "strictly kosher" than "non-glatt" produce, and, again, why mislead someone into buying glatt kosher produce?