Woah, in one sentence you claim about PHP devs feeling the need to go OO and then the next sentence you extol the virtues of ZF? ZF is all OO, all the time.
>because you can easily use it without buying into the whole MVC and routing paradigm
As much as I think the zend framework is terrible, you can pick and choose whatever bits of it you like and ignore the rest. There's no working around assumptions or anything, it is just a normal way of using the framework.