Yes, this is actually the correct way to do it.
It is done by configuring the site bindings in IIS.
In your IIS site, right click the site and choose Edit Bindings..
In here, you will have each of the domain names that your multi-store site uses.
If you have SSL for each domain, then you also need an https type for each domain:
TYPE HOSTNAME PORT ADDRESS
http domain1.com 80 yourwebsiteIPaddress
https domain1.com 443 yourwebsiteIPaddress
http domain2.com 80 yourwebsiteIPaddress
https domain2.com 443 yourwebsiteIPaddress
http domain3.com 80 yourwebsiteIPaddress
https domain3.com 443 yourwebsiteIPaddress
So, all traffic to each domain will resolve to same nopCommerce installation...and the nopCommerce uses the information saved in "Stores" settings to show correct version of the website(store) to each visitor.