1) Not able to make a purchase, due to; product hasn't been released for sale; shipping restrictions (online stores) or product is out of stock.
2) Market availability; product is heavily advertised through national / international media e.g. magazine and satellite TV. etc. but isn't available in your local market.
3) Everything Money can't buy, something out of reach!
1.a) You attempt to shop on an international site, but you have to cancel your order prematurely due to shipping restrictions. Hence the site becomes "unshoppable" for you.
1.b) A product has been launched but won't be any time soon available for sale. Until then product will bear the status of unshoppable.
2) ACME-INTERNET advertise nationally that they have got the fastest internet services "nation-wide"-- further inquiring tells you that it's only available in some area, and won't be available in your area until next year. Hence, product or service becomes "unshoppable".
3.a) JUST EVERYTHING MONEY CAN'T BUY OR YOU ARE NOT ABLE TO AFFORD. (e.g. love and exclusive memberships)
3.b) A girl who claims that money can't buy her love.
3.c) Someone married, engaged or in a relationship, not responsive for a date. is someone who is unshoppable.