Humiliation like guilt is a feeling about a feeling. Everyone feels the primary feeling, i.e., the pain, stimulation, pleasure, etc. But, not everyone gets the same secondary feeling, i.e., humiliation, about their primary feeling.

So, your premise that that all BDSM is based on humiliation is wrong. There is nothing humiliating about service, etc. if it is in the person's DNA even though others may think it humiliating.

Feeling about feelings are societal and not always right.