Seemingly not a completely senseless choice for wireless devices, since there are many reported cases of USB 3 creating interferences in the 2.4 GHz range, example:
If shielding the USB 3 device doesn’t work, the usual workaround is using an extension cable to have the device farther from the router, but even this might not work, and the only way out (ugly workaround) is using a USB 2.0 hub or cable.