Is it a bad practice to create a site collection in Central Administration's web application? Since it can only be created through PowerShell (not through the UI), it makes me think there is probably a good reason for not allowing it. We had the idea of creating a type of company admin site that would contain things like our Config Store, Content Types to publish, etc. The reason we though to use central admin's web app is because we didn't want the overhead of another web app process running. Any thought?
The central admin apppool is running under "Farm account", which means full-and-complete control over your complete farm... So you probably should not want to run anything else in that web app..