Trump was "prostituting himself to feed his ego and gain power" when he ran for President of the United States.
Sex work researcher and writer Gail Pheterson writes that these metaphorical usages exist because "the term "prostitute" gradually took on a Christian moralist tradition, as being synonymous with debasement of oneself or of others for the purpose of ill-gotten gains".
There are about 42 million prostitutes in the world, living all over the world (though most of Central Asia, the Middle East and Africa lacks data, studied countries in that large region rank as top sex tourism destinations).
Another explanation is that prostituta is a composition of pro and statuere (to cause to stand, to station, place erect).
Those offering services to female customers are commonly known as gigolos; those offering services to male customers are hustlers or rent boys.