Hmmm, well...it doesn't have to be "overnite", a few hours seems to be enough. I think I'm not understanding the problem - you mix some Bentonite with distilled water and keep the 'slurry' in a quart canning jar, put the produce in a pan, and add a few tablespoons of the Bentonite slurry and let it soak a few hours. That seems a whole lot easier than scrubbing to me (so I guess I'm missing something).
Some say that h202 works (it might?), but I don't understand how it removes poisons from the skins (or deeper than the skins). Maybe someone else understands the 'science' behind it (like Grzbear, my 'science hero'!).
Hopefully others will chime in with other options. I really don't know of anything else that would be 'easier'.