In some areas of the city of Barcelona, the method known as "door-to-door" is being experimented with, which means you throw out the trash at agreed-upon times and days. Mondays and Wednesdays, for example, organic. There are usually always two bags. Organic and glass, plastics and general waste... The general waste and organic are the crux of the matter. I live in an area where we have this type of collection. But in this area, most homes have a door, at street level, that can be opened from inside and outside, where the bag is left until the garbage collectors pass, to avoid animals: wild boars, dogs, or cats. Also, because this way, the bag can be left a little before the collection time.
The question, if we are talking about a large city like Barcelona, is whether or not there are containers nearby. If there aren't, the non-athletic grandfather won't be able to go throw the bag in other less sustainable neighborhoods. The busy worker, even if athletic, won't be able to take it on public transport or on their bicycle either. The solution is, of course, to leave the bag inside the house (in the kitchen, if you have space) until D-day and H-hour arrive. There are bags, like those for plastics or paper, that can wait without offending. The organic one is another matter. And the general waste one too if the inhabitants of the house have a small child.
If on Wednesday you make salt-baked fish and watermelon for dessert, you won't be able to throw out the organic remains until Friday, and if global warming is progressing at the rate we all know, by Thursday your kitchen will be full of flies. If you, who made salt-baked fish with watermelon, have a small child, you will see that the small child will do what all small children do, which is contribute to the diaper business. Diapers are a fetid material, impossible to keep at home. And you can't take the child out to poop, like a dog, and you can't take the material down in the elevator to deposit it in a street bin (everything is thrown in street bins) because Greta Thunberg would cry and the neighbors and the doorman would too (for different reasons).
There are two solutions. The first, that they let you throw out organic and general waste every day. The second, more drastic, being able to throw out the child on a Monday or Wednesday, along with the fish and watermelon. The diaper, especially, the next day.