1.
Why am I walking around town backwards? My physical therapist said it would help. My injuries have just been getting worse, and the stress and tension of everyday modern life isn’t helping.
2.
Why am I walking around town backwards? Dude, I’m just preemptively turning my back on everyone.
3.
Why am I walking around town backwards? Well, mostly so I avoid looking people straight in the face. So nobody recognizes me, you know? Except, now people walk up behind me, all facing forward, and then I have to walk real fast to get away. Dang.
4.
Why am I walking around backwards? To make people get out of my way, instead of me getting out of theirs. I’m sick of always being the bamboo that bends. Screw that. Now I’m the blind steel.
5.
Why am I walking backwards? I want to see what’s behind me… but it doesn’t really work. What’s behind me is always behind me, no matter which way I turn. Crap.
6.
This is going to sound crazy, but I think I have some kind of magical “kick me” sign pinned on my back. This one is kind of a metaphor. I mean, I have this feeling that something is wrong with me where people are laughing and secretly planning to make my life hell.
So I walk backwards. That way, people see the sign, and they have to react quickly if they want to punish me. If I walk forwards, someone might walk behind me and get a bunch of time to think about whether they want to kick me. They might hear my conversations, or just detect my mannerisms, and want to shove me down.
Nobody wants to waste energy to shove a weirdo who’s already walking backwards into traffic, right?
7.
Why am I walking backwards? A trick, so that someone asks me what the hell is wrong with me, maybe. I’m so isolated lately. I’ll take any human contact, even someone angry at me after I crash into them.
8.
Why walking backwards? Simple. I don’t wanna see how I’m gonna die. This one I don’t mean metaphorically. I guess it’s more to remind myself that I can’t see the future very well at all.
9.
I walk backwards even in the dead of night, back into the black uncaring. Sure, people probably think I’m some kinda crazy drunk; but who cares. I get no satisfaction from being too drunk to walk, so I walk backwards sober. Better for thinkin’.
In the late night, there’s less people. Backing up into the unknown, I can think about my own questions, instead of yours.
10.
Fine. It’s so nobody can see when I’m crying. That one’s pretty self explanatory, no? Sorry. I know I’m supposed to hide it.
11.
Why am I walking around town backwards? It’s an elaborate attempt to rewind time. Maybe if I walk enough miles backwards, I’ll somehow see my past and my mistakes.
Maybe I’ll be able to rewind back and pick out the good parts. Relive them.
Maybe I just want to walk backwards. Is that okay with you?
nil script 
I like this style of writing quite a bit, the repetition works well on many level. I also thought as I read through it what if you just repeated the question “why am I walking backwards?” only once or twice and then each subsequent time you dropped a word. “why am i walking back? why am i walking? why am i? It would work pretty well with your stanza progression…