With a vanity-URL you have the opportunity to set your landingpages with your own domain name.
For example https://news.companyname.com/christmascelebration
With these URL's its easier for the reader to understand your invitation and visit your landingpage. Also you reduce the processing effort which occur, because the reader understand the link more and don't have to contact you over mail or telephone.
The standard vanity-URL for eyepin is: https://[accountname].eyepinnews.com/eventname/.
To have a higher recognition value, eyepin recommends to set up a Sub-Domain:
for example https://news.companyname.com/.
This sub-domain can used for microsites, but also for the newsletter-dispatch and picture-URL's.
You can ask your account-manager or at email@example.com for costs for the maintenance and implementation for the sub-domain.