Is it possible for an external device to burn out the USB port?

I think the available current of the USB port is 500 mA. If a USB device can work with a current of 500mA ~ 600mA, is it possible for it to burn out the USB port with 600mA current (larger than the safe 500mA) when connected? Or the port can never provide a current larger than 500mA?
Thank you.
P.S. The USB device I worry about is a pair of USB warm slipper (to be worn on feet in cold winter). Its label reads "5V / 2.5W", which should be safe. But I once connected it and a mouse to a USB hub, then to a single MBP USB port, and the mouse stopped working in a few seconds, and came back normal only after I switched it to another port. Now the slipper is connected to a port by itself, but I am just afraid that the USB slipper can go malfunctioning all of a sudden and drain a lot of current to burn the USB port.

...But I once connected it and a mouse to a USB hub, then to a single MBP USB port, and the mouse stopped working in a few seconds, and came back normal only after I switched it to another port....
Likely the hub is only barely able to handle the 500mA requirement.  Many powered USB hubs have "cheap" power adapters and can't handle any high surge situations.  Many devices like heating elements and motors have "surge currents" where the initial powering on of the device has a much larger current flow than during normal usage.  Think of it like riding a bicycle.  You have to push hard on the pedals to start off, but it's easier to pedal after the bike is moving.
...Now the slipper is connected to a port by itself...
If you mean the device is plugged into the Mac's USB port, then you should know that all Macs for the past few years provide more than the 500mA minimum for USB.  Some other computers also provide higher power.  But most USB hubs I've seen were limited to 500mA.
If you are plugged into the hub, not the Mac, then the power adapter for your hub may be barely adequate or possibly even defective.
...but I am just afraid that the USB slipper can go malfunctioning all of a sudden and drain a lot of current to burn the USB port.
IMHO, I would stop using the heater with any computer USB port.  There is always the possibility that eventually something could short out in the heating element and cause a catestrophic surge through the USB port.  The electronics in computers are quite delicate and I'd be paranoid about the device damaging my computer.  (BTW, I have an electrical engineering background so I'm paranoid about power issues all the time anyway. )  Even if the heater is plugged into a hub, the surge current could damage the other devices plugged into the hub.  While not as catastrophic as a dead computer, I'd still be irked to have to replace my mouse, digital camera, printer, webcam, etc.
Instead, I recommend plugging the heater into it's own "power adapter."  One of those that give a USB port to charge a cellphone or whatever.  Plug the power adapter into a power strip.  Place the power strip in the floor next to the slippers.  That way you can conviniently turn the strip on and off with your toes as you're putting on your slippers.

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