From a psychological perspective: Maslow's hierarchy of needs.
From the base to the top of a 'needs' pyramid, the suggested driving forces for human behaviour are:
5) Physiological: water, shelter, food, sleep etc.
4) Safety and security: health, stability etc.
3) Belonging: friendship, intimacy, family etc.
2) Esteem: respect, confidence, achievement etc.
1) Self actualisation: purpose, morality, creativity, spontaneity etc.
Rich and powerful people are perceived to be placed somewhere near the top of the pyramid. Attraction and relationships with these people becomes logical. A quick and lazy way for others to fulfil their own needs and wants when they are at the bottom of the hierarchy.
In other words, social climbers and gold diggers! lol.