Eventually, physical shops won't exist anymore. Sad, but true.
Unlikely... shops which aren't required in order to serve a particular need purpose will suffer... shops in general won't necessarily.
While there is no big need to have physical shops selling DVDs, CDs etc... if you want a suit to be measured/fitted then some interaction with another human could be useful. Convenience stores are likely still going to be around for a while, supermarket chains have pushed into this area too for obvious reasons. But yeah any business owner, whether large or small, wanting to sit on their arse, expecting a free lunch from going through the motions of stocking their shelves with some product and selling it on can certainly expect some competition. If they're not willing to innovate/compete then their days of getting a free lunch are likely going to be over sooner rather than later...