I don't think Google claims any copyright on the Wikipedia snippets. You can share them just like you can share the original. They also give a link back to the source and clearly mark them as Wikipedia content. What more do you think that they should do to satisfy the license terms?

Arguably the entire generated page is a derived work, in which case the whole page should be CC-BY-SA not merely the snippet.

On the other hand, arguably incorporation of the snippet (as the incorporation of context for other pages) is permitted in some way other than licensing (fair use?), in which case the terms of the license wouldn't apply.

I would have to think harder to have a well-formed personal opinion.

> What more do you think that they should do to satisfy the license terms?

Just depends if the snippit is over the fair-use threshold I guess.

If the share-alike license allows segregating content into frames within one page then it is ok too.

Maybe you should familiarize yourself with the creative commons licenses. They allow all kinds of use, as long as (in the case of BY-SA) you mention the original author and share derivative works under the same license.

Fair Use is not a concept in most jurisdictions btw.