Separating items increases the potential for recycling. Only putting bins out when they are full reduces energy consumption by collection vehicles. Purchasing recycled products will increase the need for recycling.
Other countries have sets of bins for a number of occupancies, different bin for different waste, improving recycling. Multiple households using the set of bins, thus reducing the number of bins. But would we walk down the street to use them? Is our need for convenience part of the problem?