No help, just comiseration.

My oldest daughter, comes with me, so I am forever looking for something she can sit down on to go pee or poop - logs and rocks are our favorite perches thus far.

In terms of finding a place to go, I haven't been tempted (yet) to bring an entrenching tool, which supposedly offers a seat when turned into an upside down "L" shape (handle on the ground, sit one cheek on the shovel blade).

Since they're calling the breaks anyway as the slowest/weakest members of the party, I don't get particularly fustrated by this yet...