With regard to the place I went the other day, they had 2 fairly new, pretty nice cars sitting in the driveway... so obviously it's not a huge economic issue... and besides, what does it cost to put your garbage out for pick-up? Let alone cans and copper pipe... when the guy came out to look at the job (without a shirt or shoes)... that's bad enough, but for him to spit on the ground in front of himself and then keep on walking... I'm sorry, but that's a bad one.
As far as sanitary issues go... I used to have another client, land mines ALL over the place from his 3 dogs. Go into that house, and the smell was terrible... the dogs would be in cages, and the cats would be eating off of the kitchen counter. Not the type of kitchen I'd want to be recieving a meal from.