I don't recall Earl being shown in any of the promotional trailers.
But anyway, why do you think Earl is portrayed negatively?
In my opinion, Earl's death is presented in the film as being a very tragic, awful thing. If the film had no sympathy for Earl, his death wouldn't have been treated as tragic.
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I have another thought too. You know how character names tend to have some significance?
Ennis del Mar = Island in the sea. (Isolated and lonely)
Aguirre = Eagle eye. (Authority figure. Observing from above.)
What about the two men Ennis described? Not Tom and Andrew, Jim and David, Eric and Steve, etc. But Earl and Rich.
Earl = minor royalty, a man with land, wealth and distinction.
Rich = wealthy and blessed
If only one man in that couple had a name with such happy implications, I'd be open to the idea that maybe they were random name choices. But it's too much of a coincidence that both men have such names.
So why did Proulx pick these names? The implication is a positive one, IMO.