You want to use only lists excluding campaigns
If for any reasons you want to use suppressionlist.app to manage list opt-outs without linking to a campaign, this is possible with some simple instructions.
Simply do not provide Opt-out / Unbubscribe links including the campaign ID, in other words leave it blank so that the opt-out will be connected only to the List ID.
An unsubscribe link for a campaign will look like the following.
Now simply remove the “&c” from the link.