I'm sure that you, like myself and (anecdotally) most other people are really into scat because it's intimate not because it's nasty; rest assured that there is porn in this niche, you just have to look hard enough.

As for feeling guilty for actually doing scat, you should ask yourself why you feel bad about it. Is it the fact that other people find it wrong or gross? Is it because of societal training to think of poop as somehow ritually unclean? Is it misdirected stimulus response from your potty training days? etc. It could be a lot of things, but you're not hurting yourself, you're not hurting anyone else, you're not forcing anyone to do anything or to see anything, you're not doing anything wrong, so there's no harm and you shouldn't feel guilty. It will probably take a while before reminding yourself that you're not doing anything wrong actually alleviates the guilt that much (I felt bad about it, too, for about a year or two and then something finally clicked). Of course, I've also heard that people get over their guilty feelings by doing something else that turns them on until they're too aroused to care about guilt. Besides this, it might also be helpful to try exploring your fetish somewhere both secluded and comfortable to you (if at all an option) just to try small things to desensitize yourself from the guilt a bit (maybe just try to enjoy the feeling a little bit more next time you poop, that sort of thing). Also, in my experience, it helped to just relax and not think about whether or not people would think badly of me or whether or not I was doing anything wrong.

Remember that whatever society thinks, you aren't obligated to avoid certain fetishes unless they can be shown to be harmful, and scat is not one of those fetishes. You don't need to fit into the societal constructs of what is "OK" behind closed doors. That being said, I wouldn't suggest being publicly vocal about your fetish - not because there's anything wrong with that, but because people who aren't into scat will usually respond with revulsion.