In cPanel the addon domains are hosted off the subdomain which points to public_html/sub/
If you want to point a domain to a folder like public_html/another/place/ then this requires manually reconfiguring apache web server. This is not recommended but some clients do like to do this. Please note there is one time $15 charge for it.
However if you use your control panel to add the domain, there is no charge for it as long as you are within your allowed quotas of add on domains, which is unlimited for our newer plans.