I can accept that the EU is an evolving thing, and it's structure and direction may change. However, Cameron got a few concessions from the EU that would have come into force if we had voted remain. One of those concessions was that Britain would not be forced into any greater union and that membership of the EEA would not be lost by staying away from any further integration. So whatever the evolution of the EU, Britain would not change much.
I think this is the motivator for many leave voters, nothing much would change with remain, if you feel a bit downtrodden, why would you want things to remain the same? The answer I came to, was that it is not the EU that is the cause of most of our problems, and in fact does many things that are of benefit.
Out could mean little change if we are out like Norway, or massive change if we are out like America.
I believe, and I don't have the details at hand, that Cameron's concessions were not set in stone. I am sure it was proved/stated that these "concessions could be/would be ignored after the referendum. I do wonder whether paying lipservice by Dave and Angie, was a plan to keep us in the EU.
Obviously the majority of the voters were not fooled.