The simple reason for wheels is
a)stuff needs to move
PLUS
b) a wheel carries weight. The mechanic system itself supports the weight, you do not need to put any energy into the system to support the weight (as on legs, no matter whether biological or technical).

This greater energy efficiency is a huge advantage over legs, and the reason why we move faster on bikes than on legs, for example: We spend our power on forward movement and almost nothing on supporting our own weight (only on the spine).


That's why I make the compromise at something on wheels that's either meant for roads or meant to be crew-portable over obstacles (even walls).

There's no universal solution anyway. You don't want to use mules in jungles where you need to create a path with a machete, for example.