Some devices do indeed have a higher power draw requirement. If you own a mac, you may have already discovered this when trying to plug certain items into the keyboard USB ports only to be told the device power draw is too high for those ports and you need to plug it in elsewhere.
USB was not intended to be a long-range connection, the designers never set out to compete with well established mechanisms such as Ethernet and RS-485. I've never used one myself yet, but there are USB Ethernet Hubs on the market which might satisfy those wanting the distance of Ethernet but the connectivity of USB.