Weeding or Harvesting Fertility?

A lot of my weeds just get pulled and then dumped on an unused patch until they get relocated to the compost heap - at least it keeps the moisture in the soil while they're there and then I get more mass to put on the heap in one go. I try to get a barrowful, but it's partly because I can't be bothered to push the barrow up the hill to the heap until it's full!
Many weeds get left to flower for insects even though I know it means more weeds in the future. Fortunately I can afford the time to do more weeding and feel that insects need all the help they can get. And they (weeds and insects!) can be quite pretty!!
I make comfrey tea - at the moment it is made in an unlidded container close to the compost heaps which is nearer to a new house than ours. We'll see how nice the new neighbours are before deciding to get a lid !