if the discussion is about putting code in your DB that apps should SELECT out and then run arbitrarily, I'd agree with you on moral grounds -- but there are lots of situations where the "data" for one application is "constraints" for another application.
CMSs are a great example of applications where the person writing the application doesn't know what kinds of constraints the end user needs for their data, because the "content" is different for each installation -- so the "adminstrators" of the system enter the constraint data, and the "users" of the system enter the content that conforms to those constraints.
Surely you wouldn't suggest that everyone who wants to install/maintain a complex application needs to write code to define how they wnat to allow others to use that application? you might rgue "that's what configuration files are for." but how is puting that information in a configuration file really any different then putting it in a database?