Using {tags} in a template will get *all* the tags, not test for existence of a particular tag.
Starting a "more than you wanted to know" section....
The easiest thing to do is to create a custom text column (not tags-like) and enter the folder name in that. Then use {#column_name} in the template.
You can avoid the extra column by using a template program to check if a tag is there and return the folder name you wish to use. This is rather complicated. The construct would be something like
Code:
{tags:'first_non_empty(
in_list($, ',', '^news$', 'news_folder', ''),
in_list($, ',', '^foo$', 'foo_folder', ''),
in_list($, ',', '^bar$', 'bar_folder', ''))'}
You can simplify the above if you don't care about submatches, meaning you don't have tags of the form "my_news" or don't care if you get both "news" and "my_news" when checking for the tag "news".