The reason why fish from Townsend and the park differ is stocked v. wild. Stockers seem to be usually whiter/pinker than park rainbows.
Take a look at this site for some good pictures of each species
http://www.troutnut.com/pictures/of-trout
Keep in mind that fish in different streams can look different, as well, due to the fact that the breeding is not controlled in the park (like hatcheries), so some variation has crept into each species.