Bacteria evolving to secrete a soap-resistant compound doesn't sound far-fetched at all. Such compounds clearly exist already (e.g. pigments that don't wash off).
Thinking about this more, I suspect there already has been some selection in this direction, but that it has little to no public health impact, as this defense is not useful in places where infections are typically a problem. Indeed, our body is teeming with bacteria (mainly in the guy) that are in fact beneficial, and they've presumably managed some resistance to shear stress and extreme chemical environments (e.g. high acid).
Thinking about this more, I suspect there already has been some selection in this direction, but that it has little to no public health impact, as this defense is not useful in places where infections are typically a problem. Indeed, our body is teeming with bacteria (mainly in the guy) that are in fact beneficial, and they've presumably managed some resistance to shear stress and extreme chemical environments (e.g. high acid).