Dog walker here. I will put poop bags in any convenient receptacle nearby, and I see absolutely no problem doing so. Anyone passing my own bin can put whatever they want in it as long as they don’t fill it past my ability to use it. If the bins are put away back off of the street or sidewalk area, though, I won’t bother a homeowner to traipse onto their property.
Best poop moral conundrum I faced? One particular house has a very steep embankment from the street down to their yard. My dog squatted at the top of the street, and his poop tumbled slowly down the slope, like a brown slinky, for a good 50’ ultimately coming to rest pristinely placed on the decorative flagstones of their patio. I pondered whether or not to try and scootch down the slope with dog in tow to pick up the intrepid poo, decided against, and continued on my walk.