Thanks everyone. We had a similar but not the same experience in St Petersburg a few years ago. Putin was not happy with Obama/US and we sat in line for hours as the Russians looked over every passenger and every passport like they were told someone hid a $100 in one of them. Most of us missed half a day and got to the Hermitage hours after it opened - and of course it was full of other tour groups by then. Our independent tour group guide would not say much but we could tell they were pretty exasperated with what happened. I suspect with the current political climate the Chinese are doing the same.
It is a long way to go to have to stay on-board but it is also a long way to drive to Atlanta - then stay several days to complete a visa process. Between the traffic and politics I would not be comfortable doing Shanghai on our own so we will do a tour - even though I know at least 2 hours of it will be in some idiotic silk shop. I was in Beijing some years ago for a meeting with a day-tour as part of the package. We were headed to the Great Wall in the morning and first stopped at a "pearl jewelry shop." We Americans were too worried about being "ugly Americans" to say much but thank goodness the Malaysians on the tour were not worried about that - they ripped the tour guide a new one and we got out of there in less than 30 minutes!