Lyle, as far as the cat food in the diaper scene? The first reading made it sound like the bum had a thing for eating poopy diapers. Now that you’ve explained it, I get it. It inspired me to come up with this scene:

Bum in cafe, sits at table with coffee. Beautiful woman comes in. He looks at her and we slip into his daydream. Bum and woman in sunny kitchen, she is heading off to work so she throws half of her bagel in the kitchen trash. Our bum friend eyeballs it nervously, drums fingers on table, says “bye honey, have a good day, so long, bye bye” while his eyes are darting between her and the garbage. She leaves the room and he runs over and eats the bagel out of the garbage, muttering about how foolish people are to throw away food.

Cut to our bum friend squatting in the bushes in front of the house, a nice suburban house with lawn. Wife drives up from work and sees him crapping in the bushes, screams, and points at him, saying, “Get out of here! Get out!”

the wife’s face melts into the cafe owners face, he is yelling at the bum to get out of the cafe.

end of act.

More random thoughts on homeless:

Homeles are a large category. Break them down…

bum refuses to work due to anti-capitolist philosphy

Then there are those who are on the streets due to drug/alcohol abuse, or a tragic accident/mental illness keeps them from functioning in office settings “the real world” of paying bills etc.

rubber tramp – bum who lives in a car or camper

hobo- moves around, will work if they have to.

gutter punks/squatters – young runaways who band together on the streets and live in abandoned city buildings, try to be political, sell weed on Haight street, spare change people

working poor – families or single parents with kids who don’t have homes, but work, end up in shelters.

we can have our hero be a bum. I like that this guy has given up on capitalism but not democracy.

He can weave in and out of these other types of homeless people’s lives, showing us the different communities on the street. The drug dealers who come into the homeless comunities, the pimps who offer “protection” to homeless women
the guys who are sober (or drunks) and living in flop houses but hang out on the streets all day and most of the night, and I’m sure there are more to discover.