Why we cant ship to every country.
The legal status of bitcoin varies substantially from country to country and is still undefined or changing in many of them.
However, the use of bitcoin can be criminalized, and shutting down exchanges and the peer-to-peer economy in a given country would constitute a de facto ban.
According to the United States Library of Congress, an "absolute ban" on trading or using cryptocurrencies applies in eight countries: Algeria, Bolivia, Egypt, Iraq, Morocco, Nepal, Pakistan, and the United Arab Emirates. An "implicit ban" applies in another 15 countries, which include Bahrain, Bangladesh, China, Colombia, the Dominican Republic, Indonesia, Iran, Kuwait, Lesotho, Lithuania, Macau, Oman, Qatar, Saudi Arabia and Taiwan.
The legal status of bitcoin (and related crypto instruments) varies substantially from state to state and is still undefined or changing in many of them. Whereas the majority of countries do not make the usage of bitcoin itself illegal, its status as money (or a commodity) varies, with differing regulatory implications.. While some states have explicitly allowed its use and trade, others have banned or restricted it.
You can read more about specific country regulations at Wikipedia here: https://en.wikipedia.org/wiki/Legality_of_bitcoin_by_country_or_territory and here: https://www.loc.gov/law/help/cryptocurrency/index.php