Probably because your USB flash drive isn't USB 2.0, or your USB ports on your PC's motherboard aren't USB 2.0, or both.
USB 2.0 supports theoretical transfer rates of up to 480Mbps. The older USB specification (1.0 / 1.1) only supports theoretical transfer speeds of up to 12Mbps. I say theoretical because the more USB devices connected to your PC, the greater bandwidth being used, which can result in lower speeds. Plus you'll very rarely see speeds as high as 480Mbps being reached.
But still, USB 2.0 is much faster. All devices need to be USB 2.0 compatible, and be High-Speed not just Full-Speed compatible (which some manufacturers stamp on particular USB products, making it easy to mislead).
Difference is a High-Speed device can transfer at USB 2.0 speeds...whereas a device with Full-Speed compatability can be used in a USB 2.0 port, but can only operate at USB 1.0 / 1.1 speeds.
Both the USB hub and devices need to support USB 2.0 High-Speed.
|Desktop PC| |Macbook Air 13" (Mid 2013)|
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