Yep, there’s a setting you can activate when you create the group that allows members to join and leave groups freely.
If you go this route you may also want to make sure that the groups page is really easy to find for those members. One way to do that is using the Custom Headers Links theme component and adding a link that goes to the Groups page.
you can do this by adding something like this to the Theme Settings after installing the theme component.
Groups, groups, /g, vdm, blank, remove
