When I first took in Benjamin, he really did not want to eat his pellets. I feed American Pet Diner Timmy Pellets, but I suspect Benjamin had been used to getting either alfalfa pellets or junk-food pellets with the extra bits in it. He absolutely did not want to eat his pellets!
After a week when he wouldn't eat them (I would empty the dish at feeding time and give him fresh, every day), I decided to try to trick him. I got some oats, and added a small amount (less than a tablespoon) to his pellet ration. It worked at first, he would go for the oats and end up eating some of the pellets, too. After about three days, though, he had become expert at getting out every oat and leaving all the pellets! Since this had been going on for three weeks or more, and he really wasn't eating as much hay as he should have been at that point, I continued with the oats. After a couple more weeks, one morning I got up and the dish was completely empty! I continued mixing the oats with his pellets for two more days, then stopped, and he just kept eating the pellets from there. (He was underweight when I got him, so I continued giving some oats daily, but I do them at bedtime now. I am in the process of weaning him off of those, as he's put on a good amount of weight now.)
I think for him, it was just a matter of getting hungry enough. He has gotten used to the pellets now, and runs to his dish a meal time like everyone else.
I feed all of my rabbits about 1/4 cup of pellets each day. They're all adults, and range in size from 4lbs (Tobi and Nick) to 5 (Benjamin) to 6.5lbs (Amelia). I use a 1/2 cup scoop, and mound it up just a bit for Nick and Amelia because they share. Benjamin gets about half of the scoop, and Tobi gets just under half of the scoop. They also each get about 2 cups of salad daily, and get unlimited hay- which they eat TONS of.
They never get more pellets, even if they finish all of them. I just make sure they always have a full hay rack, and I know they won't go hungry.
(Well, there was that one time, when Nick sat staring into his empty dish, then occasionally looked up at me then back into his empty dish. I did have to give him more that time. He has trained me well. LOL.)