if the shop is 10 km away vs 30 km away

It’s nothing at all like that. The moon is 384 megameters away. Mars is 54000 to 150000 megameters away, depending on orbits.

So it would be like 384 meters vs 54-150 kilometers.

Escaping the gravity well on the moon is also much cheaper.

[In terms of infrastructure and accessibility, it’s really no contest. The Moon is closer, always has a view of Earth, can exchange signals and deliverables hundreds of times more quickly than can be exchanged between Earth and Mars, and is easier to land on and take off from. Certain infrastructure could be easily shared between the Earth and the Moon, such as the internet, whereas Mars would likely, due to its remote nature, need its own standalone infrastructure.]

But they are both far enough away that is doesn’t really matter.

The difference is huge. The moon is practically right next door to us (384 megameters). Mars closest point to Earth is 54000 megameters.

It’s like having a friend living 384 meters down the road vs living 54-150 kilometers away.

500,000 mph is 800,000 kilometers/hour or 800 megameters/hour. So it could reach the moon (384 megameters) in under 30 minutes. It could reach Mars in 68 hours or less than 3 days when Mars is closest to Earth (54600 megameters).