There is some kind of inherent ambiguity about a halacah in the Rambam. [נזקי ממון פרק ב] He holds if a string gets attached to  a chicken and it is walking around and breaks vessels, the owner of the chicken pays 1/2 damages. And he brings a support for this view from בור המתגלגל ברגלי אדם ובהמה [a hole that is rolling around in a public domain by the feet of people or animals.].
That proof seems to work against what the Rambam is saying for נזקי בור [damage caused by one digging a hole in a pubic place] are not obligated for damage to vessels. considered
If it is considered damage caused by "feet", then it would not be obligated at all in  public space.

I am being short in this above paragraph because I am not sure how to answer this. The Gemara asks what does  צד השווה in the mishna come to include. Rava says בור המתגלגל ברגלי אדם ובהמה and it is learned from בור ושור. Is it possible the Rambam could hold once something is learned from צד השווה It would get the חומרא of both? In our case that would be an obligation in רשות הרבים  and also חייב על נזקי כלים?