Standard power to / from a computer USB port is 500 ma. So, very true, if the hub is not separately powered, i.e. with an adapter plugged into 120 volts, using it would be problematic at best and could fry parts of your computer.
I use a 4 port wall wart adapter, rated 2 amps, plugged into a power strip. Cost about $15, Amazon has a variety to pick from.
Conversely, if it is a powered hub, just plug it to the wall and not the computer. Since you're not transferring data into the battery, why risk damaging the expensive stuff?