The short answer is no. Model releases are not necessary for the publication of editorial work, only commercial. Having each participant asking local persons to sign releases they cannot possibly understand would not only be awkward, but would gum up the works.
Concerning any photo contests that claim they need model releases for editorial work, they don’t. We advise contacting them before submitting your images to find out if such a rule is actually enforced, and/or if it applies to your particular image categories.