Hmm, at the risk of being lumped in with all those other terrible mothers, I shall stick my neck out and say that when I used disposables, and now when I use them on my older dd, I don't change anywhere near as often as I do with cloth.
There, I said it.
I don't think what you are talking about is at all unusual. And sorry, I don't think it's as awful as you seem to. I"m not talking about only using 3 a day, but heck, I'd never change a sposie every two hours. And if I"m out at a park day and dd#1 is in sposie (won't use cloth), I"ll change dd#2's cloth, but not dd#1, unless she's really really wet (usually isn't).
Why? Because firstly both my kids HATE being changed. It's a big deal for them, and for me. It's different with a tiny baby, of course, although I never changed sposies every hour either at the baby stage.
I never change a nappy at night, either cloth or sposie. (unless soaked, but they have never been, either cloth or sposie)
I always change poop as soon as the child will let me. You know, they don't think it's as gross as we do, or at least, my kids never did.
They will often put up a fight and run away insisting they haven't pooped when I know they have. Anything to avoid being changed.
I feel terrible every time I throw a disposable in the bin. I wish I didnt use them, and I certainly don't want to start throwing them out every hour or every two hours. I hate what I"m doing to the landfill enough already.
As for wet or sore, well, the truth is that in a sposie, dd is neither. Dd#2 is uncomfortalbe in a wet cloth nappy and is happier to be changed (usually, anyway). I know about the chemicals, and beleive me, if dd wasn't special needs, I'd have switched her to cloth three years ago. But most parents don't know or care about the chemicals. What they care about is that their baby feels dry (whcih they do in disposables, for sure). And yes, they care about the cost. I"m not poor, but I hate the money I spend on disposables, and don't want to spend more than I have to.
Now, I said it. I think there are far worse parenting practices for us to get worked up abotu than how often someoen changes a disposable diaper. JMO, though!