Part of the town (not where I lived) was really wealthy: the kind of people who would put out their television that was 2-3 years old, working fine but not the latest model. Or they'd redecorate. So, a lot of people would cruise these neighborhoods ahead of the trucks picking up. My husband refused to let me do it, which is really a shame. They tossed some good stuff.
Our town is not wealthy. We put stuff on the side of the road with a sign that says, “FREE” and it is usually gone in 12 hours. But not mattresses, not sofas that have gotten wet and not bags of trash. Those we take to the landfill or burn in the back yard. And so we resent the dumpers who don’t take care of their own trash.
Fly tipping is basically free, so your official disposal process has to match that price, or people will go elsewhere.
BUt the people have to drive *TO* our road to dump. So they already have it in their car.
I absolutely get that. I live in a very working class town/small city. When we were doing renovations on our old house, we had a big dumpster in front. We put in a lot of our own 'crap' , in addition to some old house parts and some construction debris. Other people added stuff to the dumpster (without asking) and even more, lots of people drove by and.....took things out. More was claimed by dumpster divers than left by the freeloaders who tossed their crap into our dumpster. We got a new dining room table and were able to discard the old one (antique from probably the 30's, repro from an earlier time period). The old table was in very poor condition--legs falling apart. Someone on FB had said they wanted it to use for a project but they disappeared so it went to the curb with a sign that said free. That night, a neighbor called to ask if they could have it (it was marked free and I was embarrassed I had not asked them first--they are even better than I am at making things last and repairing/reusing stuff). Their daughter wanted it--she grew up with my kids and ate a lot of birthday cake and pizza at that table. We cautioned them that it was really in poor condition but they already had someone to repair/rejuvenate it. YAY!!! Something not in the dump and owned by someone who really loved it. We added the chairs as well. This is a neighbor that I traded kids' clothes, various household items, plants from our gardens, and complaints for well over 30 years.
Our town isn't rich and they are extremely cheap--extremely. It's also a college town. It is unbelieveable the amount of stuff--sometimes actually pretty good stuff--students leave behind on the curb. I picked up a dressing table and a small table with dovetailed joints for...$15, both pieces. Yes, they needed painting but....
I understand that is the custom in your area: people just go out to some abandoned looking road and dump their junk. I thought your request was an attempt to change people's behavior. In order to change behavior, you have to make it very easy, very convenient, and give them something for their efforts--in this case, a bit of pride. I'd be tempted to start contests to see who could best re-purpose junk. Also, around here, if you purchase a new mattress, the store will take away your old one.
Do you have Habitat for Humanity in your area? They usually operate a re-store where a lot of people donate (and purchase) a lot of items. I know I have done both.