that’s like saying there is no such thing as clover honey because the bees might take in some apple blossom while they are at it.
Or that saying a jar of honey is clover honey because some bee might have flown over a clover patch.
No, that’s not what it means. Organic farms are controlled and are certified as such. You can’t keep bees from going farms that are not certified as organic. They may get pollen from your organic clover that can be contaminated with bees from outside that area. It’s not where they get pollen (i.e apple or clover) but whether it’s certified organic. Next farm over may not be.