blueshoes you said "if go organic, no point in going organic for some foods and not for others - so why bother?"
I don't agree. I buy quite a lot of organic food, but also buy stuff that isn't when I can't get what I want in an organic version.
But buying 75% organic reduces the amount of pesticides that I eat by 75% and in the case of the animals, gives them a better life as they are not intensively reared.
So I do think it makes a difference to buy as much organic food as you can even if it's not 100%.