But it's likely to be tough luck for the website if their business model depends on free search traffic from Google.
A URL does not need to reflect the site's logical structure - and coming as close as you can to "one URL for one unique bit of content" can help you in search.
Any site can do as it likes for their visitors, clearly that has always been so. So go ahead with as much complexity in your faceted navigation as you feel makes sense for your users. Still, understanding how the search engines work today can be very useful for many to get more traffic - today - and that was Matt's topic here.