People can still choose to start smoking Brit, but news laws and higher prices mean that it's not in there best interests. Which, in turn, has meant the countries with the strictest laws against smoking and the highest priced cigarettes have seen the highest drops in the number of people starting.

You can still smoke, it's just not really worth it to do.

People can still choose to have more than two children, and there's no law against it. It's just simply not in their best interests to do so.