Let's not be naive, people are most prone to do what is easiest. If it requires a departure from what is their norm, they don't want to do it. Recycling involves more effort than chucking everything in the same garbage can. The only way to make people recycle is to mandate it. Similarly, the only way to make people choose the more expensive option of using biodegradable bags is to ban regular plastic bags. People will begin bringing/buying reusable purpose made bags to grocery stores.. For garbage, depending on the municipality, they may or may not be able to use regular plastic garbage bags. For recyclables, the city may mandate biodegradable. It all depends on what processes the city puts in place.
The bottom line is that municipality is telling the citizens of the city that they won't be raising their taxes by an extra $100 or $200 per year, which would be the new cost of eliminating the garbage, by virtue of buying into the new plan. This is probably not a big factor for cities with populations under a million, but for the bigger cities it has a huge impact on taxes. I live in one of those larger cities where garbage disposal became critical. I have one large bin for general recycling (paper and plastics), one small bin for garbage - non recyclables, and an even smaller bin for biological matter. I don't mind knowing that we are recycling 60% plus percent of our waste.