Most of the snippets use chunks as tpls (we call them that to separate them from the site Templates) to allow you to format the snippet output. You can also specify the tpl inline in the snippet tags like
&tpl=`@CODE <li>[[+pagetitle]]</li>`
Some snippets also allow you to specify a file as well. Wayfinder also provides the &config=`whatever` property, where you can use a file named "whatever.config.php" stored in the core/components/wayfinder/configs/ folder. There are several sample config files there already.
For example, by default Wayfinder uses
<li[[+wf.id]][[+wf.classes]]><a href="[[+wf.link]]" title="[[+wf.title]]" [[+wf.attributes]]>[[+wf.linktext]]</a>[[+wf.wrapper]]</li>
for each row. For your categoryFoldersTpl you would have a chunk with something like this, so that it won't have a link:
<li[[+wf.id]][[+wf.classes]]>[[+wf.linktext]][[+wf.wrapper]]</li>
You always need the [[+wf.wrapper]] placeholder; this holds the rest of the Wayfinder output to insert as the nested list in the row item if it has any children.
You'll notice that these tpls use placeholders. Wayfinder gets each resource that it is going to list, and applies the tpl to each one in turn, creating the placeholders for each resource's values. You can also use several of the resource fields, including TVs, but you need to keep in mind that these are placeholders [[+fieldname]], not regular resource fields [[*fieldname.]]
http://sottwell.com/links/wayfinder.html