Except a physical copy doesn't disappear when the person who owns the copyright decides the store you bought it from didn't sell it to you the right way.

Not quite, copyright law prohibits you from doing some things with the presentation of the information such as distributing copies and creating certain types of derivative works.

I am free to do virtually anything with the original including archive for all eternity, loan out relentlessly, sell, or chop into small sections and sell the sections.

I can even copy within certain contexts (archival copies of software, for example) and I can create certain types of derivative works (parodies and certain limited educational uses for instance).

> am free to do virtually anything with the original including archive for all eternity

You are not allowed to show to an audience a movie you bought on a dvd. There may be other examples.

You are allowed to watch it with your friends though, of course that might depend on the country you live in. In Germany you are even allowed to give copies to close friends and family members (but you are not allowed to break copy protection).

You have a point that you can provide a "public performance", but as I understand it (clearly IANAL) that is defined quite strictly and you may show friends and colleagues in a private setting at will.