The difference is that, despite being a long trip, sailing to Australia and South Africa and the USA was fairly routine, and did not involve enormous costs, both in material and to the environment (how much CO2 does lifting a person to orbit release to the atmosphere?) How much did it cost to put a trifling amount of men on the moon?

In colonial times for example it was common for a woman to go home to Europe to give birth. Will that really be feasible in mars or the moon?