Gig economy - roughly: Work is outsourced and intermediary companies (that get jobs from customers and deliver them to workers) become the controlling power in their industry, often to the detriment of customers, workers, and society.

Gig workers may benefit from flexible scheduling; however the power imbalance means workers often lose out - lacking reliable income to meet basic needs, healthcare, paid parental/sick leave, unemployment, pension and retirement benefits.
(Similar things happen with other assets - e.g., housing, shopping, or media.)

Related terms that might help:

Piece work
Platform Economy
Sharing Economy (An earlier term for pretty much the same thing - trying to give it a positive spin).