Right, and the charger is plugged into the wall which provides 220VAC. The cheap chargers are unsafe because they don't have enough clearance between the high voltage and low voltage sides of the circuit, so the isolation can fail and energize the USB port with 220VAC, for example. This is a well-known failure mode of cheap phone chargers, and it should be obvious why these shortcuts are illegal in most countries.

Teardowns of cheap USB chargers online explain what I'm talking about, for example, https://www.youtube.com/watch?v=wi-b9k-0KfE