To me it's not a matter of believing in just the one thing over the other as far as diet goes.
I believe in variety when it comes to my flock's diet and yes, a good seed mix for budgies is vital and so are fresh foods, like sprouted seeds, veggies, the occasional little piece of fruit and egg food whenever needed.
Just like you, Lyn I have pellets for my budgies and they are also free to choose what they want to eat. Usually they would only eat them with gusto when I hand feed the pellets to them. My lovebirds take to the pellets more easily than the budgies and I don't fret over this at all because I know they are on a healthy diet.
Just some FYI, not all countries sell pellets for smaller birds, so pet bird owners don't have that much of a choice (not all people have the means nor the ability to order online) and still these people are able to provide a healthy diet to their birds. I'm not radical to the point of only allowing my birds to eat pellets, personally I don't really want to go that route.
In my country, bags of pellets for small birds aren't sold, at least not to my knowledge, since I have never seen them on specialized pet stores.
I get pellets through my budgies and lovebirds seed mix from Vitakraft that has pellets in the mix.
RIP sweet Tito (Summer 2008 - January 17th 2013).
You are missed and never will be forgotten.