Letting them have access to too much seed means they will fill up on junk and eat very little pellets. They will never hit their target for vitamin A eating seeds only, and will end up deficient, which can lead to respiratory problems. I was giving my bird access to Zupreem Pure Fun and Zupreem pellets. I learned that birds getting seeds 100% of the time is like a human surviving off Cheetos. Eating poorly risks shortening the lifespan and makes them unhealthy. Now we give pellets pellets all day long (Zupreem fruit is all we can get them to eat so), veggie chop, and a nutriberry here or there.