There is a site which autamatically leaks your content on patreon if you don’t have the ‘‘charge upfront’’ option enabled. And even if you have ‘‘Charge upfront’’ enabled, it offers to leakers an option to easily import ALL your content if they support you on certain tier. Example: if your content is for +$5 patrons, and there is a $5 supporter that knows that site, he can easily leak all your contnt of your patreon page.
I don’t know if im allowed to post that site here, so i won’t just in case unless staff tell me to post it.
To avoid the automatic leak of your exclusive content, i recommend you uploading a cropped image of your pic, and sending the full version via PM. Sadly, it doesn’t help when someone really wants to leak your content and upload the pic that you sent him/her via PM.