Hey so I used to run background checks for folks. It's probably mandated by their insurance carriers, especially if you're going to be around minors.

If you really don't want to do it at all, you might be able to negotiate more solo volunteering. We had people who just signed up to pull weeds not help with the kids but that type of flexibility will depend on the organization and what they're doing.

It's totally normal to not want to comply, that happened to me a lot. Just try not to be angry at the person running it because they probably sincerely don't care they're just trying to get paid.