To the OP:
When walking your dog, you have to follow all the applicable rules and regulations.
Contact your town or county and ask what the dog walking ordinances are for your location. It may not be just about cleaning up - you may have leash laws, BSLs, and the like that you have to follow. You'll probably end up talking to one of the animal control officers. You'll not only get the rules, but how animal control interprets the rules. That will help you a lot.
Also, if you wander into a "gated" or HOA community, or special areas such as around schools, the rules can be quite different from the general ordinances. So be aware of any special signage as you are walking around. Some of these locales have very strict dog related regulations.
We go to a lot of places for trials, matches, practices or just visiting. Ranging from urban to suburban to exurban. Sometimes there is an assigned potty spot but sometimes there isn't. We couldn't possibly know what the laws and regulations are for every place we go to, but we have found that most of the time, if we act reasonably responsibly, clean up after our dogs, and don't let them wander into what are obviously front yards, we are OK.