Most of your post is utopian and maybe right that in olden days religions co-existed. Since I have not seen it first handed I cannot agree or disagree. While doing business with a Shariah state will never be a problem, however Saudi A is the worst example of Shariah rule. It is not only extreme in its view points of human rights nor does it care two hoots about minorities who work there, why even fellow muslims from other countries are treated like dirt.
Regards
Utopia is something without precedence. It is something that you aspire to but may never achieve. Sharia on the other hand is nothing like this. It is precedented over a period of 12 centuries. Was it perfect? No, but neither is democracy or anything else. Its all a matter of implementation. If its done right then people appreciate it, if its not then its critiqued.
KSA example was just to make a point that Sharia enforcing states can and do co-exist with others. As far as Saudi human rights are concerned, if you look at the annual US dept of State report, it usually criticizes the Saudis for stuff that they do to keep the Monarchy in place (putting down political dissent) or cultural stuff (Saudis treating all others except Europeans and Americans like crap). Death sentences are another aspect. I totally believe in it as do very many other Americans so while one is free to criticize this as an infringement on human rights, there are two sides to this story.
So lets not mix up the political, social situation in KSA with the purely Sharia issue. Each has to be looked at its own merit.