Capturing or "sniffing" USB packets on Windows is quite easy, if you know how. All you need is Wireshark and the packet capture driver usbpcap. Here are the steps to get you going:
Start an admin command prompt cmd.exe.
USBPcapCMD.exe to get a list of connected USB devices and which "filter monitor" they belong to:
You can either start capturing from there or start live capturing with Wireshark instead:
"C:\Program Files\USBPcap\USBPcapCMD.exe" -d \\.\USBPcap1 -o - | "C:\Program Files\Wireshark\Wireshark.exe" -k -i -