Maggie - glad you care!
I buy organic for myself as much as possible so the crix get the same stuff I eat! But wash/rinse foods anyway. If you cannot get certain foods that are organically grown wash them well. prepare them the same as you would for a child or yourself. Hey, aren't you in So. Cal??? You shouldn't have any problem finding organic and if you are into gardening could easily grow much of your own.
I am sure some folks do not bother to do this and that is their choice. I make the choice of controlling the amount of synthetic chemicals, that I or any of my critters ingest, the best I can. Unfortunately, there are certain ones we can't avoid so why not make a healthy choice when you can - for you and your herps 
here is a site with info and MANY great links!
lele
Organic
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0.1 veiled - Luna
0.2 green anoles Jaida & Jetta
0.1 brown anole - Jamaica
0.2 house geckos - Gaia & Tia
0.2 felines - Kyndra and Líta