On a clean install of Foreman, you get two copies of the "epel" snippet and six copies of the "HTTP proxy" snippet.

For epel, the snippet is automatically added in db/migrate/20101125153351_add_default_templates.rb, which adds every known snippet. It's then added as well by 20120604114049_add_epel_snippets.rb which doesn't check if it's already defined.

For HTTP proxy, the snippet is also added by 20110420150600_add_solaris_templates.rb for every template type without checking if it exists.