I know quite a few 9,10,11 year old boys who do not want to go to shul, its totally normal- what exactly is there in shul thats so attractive for a little boy who would rather be playing and having fun?
Rewarding and bribing is basically the same thing, and its sometimes the only way to get boys to go to shul.
I think its the same kind of thing as licking honey off the aleph beis when they go to nursery for the first time- it just an incentive and theyll get used to it.