Feedback Loop Servers and Bounce Servers


I would like to know between feedback loop servers and bounce servers are using the same email address or should be a different email address?
@JFOC - they will be different, for fbl's you have to use abuse@ / fbl@ and postmaster@ for each sending domain you'll be using.
For bounces you can use any address, usually people create a generic sending address, like that is used for bounces and also for sending the emails.
Please note that if you are going to use an external web api provider, say mailgun / elasticemails / etc / then you don't need to worry about these.
What happens if we don't create any feedback loop servers. Will any harm be caused. I can't afford to subscribe to sparkpost. I am just using my vps hosts built in php mailer. Thanks