You're not wrong that such things make a city less walkable, but there's also a strong argument that just punishing people, instead of, you know, addressing the underlying problem doesn't solve the problem either. It just sets up a situation where people bounce from jail (due to the realities of living on the streets) to the homeless encampment (due to unpaid fines preventing them from earning any money).

Like, the whole reason the West Oakland homeless encampment has such an enormous garbage pile problem is because nobody living there can sign up for trash service, since they lack an actual address (and likely can't afford trash service anyway). So as soon as the single 30-gallon courtesy trash can gets filled up (within hours of delivery, if experience is any guide), they're on their own until that that can gets emptied. And they provide that single can for all the trash needs of the 30 or so people living adjacent to it.

One of the core drivers of homelessness is the absence of affordable housing within efficient reach of public transit to get to where people work. So by setting up communities that are designed specifically for walking and public transit and are affordable for most directly addresses the main driver of homelessness, which in turn starves the friends-couch-to-homeless-encampment pipeline. Nobody goes directly from evicted to homeless encampment. Its a long fall from grace. Preventing the first step, by ensuring there's adequate housing near where the jobs are, helps prevent the final step.