A fresh leaf plucked after the rain in a tropical rainforest is no dirtier than a leaf of lettuce pulled from my garden. My strawberries touch the ground, which is way more of a concern. I eat those too. I also don't use sprays or pesticides or any of that.
I live in the Redwoods, classified as temperate rainforest. I collect and eat raw wild strawberry, blackberry, wood sorrel, sheep sorrel, etc. from under the canopy, and after a good rain soak they are more crisp.

I eat them directly or cook with them. Millions of people do this and have for millennia.
The inside of a urinal is way, way, way dirtier and abundant with trace buildup. But, your statement is valid: loose dirt can be removed but sticky residues or oils or molds cannot. Leaves/plants should always be examined for these reasons and others.