You can stop along the side of the road in many spots. You will find periodic rest areas with remnants of camping such as piles of wood and rock rings, but most traders stick in a convoy and arrive at the rest area together for sdded safety.
The bullseye lanterns are a good choice and needed with animals not used to pulling at night, if you want to train them, pull past dusk until they begin to become wary.
Mules and other equines may refuse to move and dig in, start kicking, panic and run, or start breying loudly, rear up, reverse, become inconsolable for a time. The aftermath of pushing a mule too hard may be lingering issues.
So the bullseye lamp gives them a bright, wide, forward view which is reassuring so they may not even care that it's dark.
I'm going to say Gundren's cart had them but you didn't need them.