When offering to help as a community service, I see no reason why they would expect people to have police training.
This isnt just ANY kind of community service like helping the Red Cross or picking up trash on the highways. We're talking about patrolling and defending our borders from illegal aliens. Some of these illegals are well armed and extremely dangerous. Sure, folks would love for Joe Blow to come and help out, but nobody wants Joe Blow to end up in a bar ditch the next morning with a hole in the middle of him because he tried to tangle with some wetbacks who decided to defend their drug packages with deadly force.