That's what I meant - with SSI, Googlebot will see the ads. Nothing to do with PR leak. Here, SSI is just a convenient way to manage the code for ads, i.e. not have to plant it in each page but call it with an include. IOW, I don't see it as cloaking.
But if you can serve a different page minus the SSI call to the ads, based on IP addresses, that's cloaking.
To answer the question about not getting the ads in the snippets, you can use clever positioning of tables so that the top row is below the main body of the visible page. You can also use CSS to do it. Ask in the CSS forum.