This isn't entirely true. FRS handhelds generally have a transmit power of 1/2 to 1 watt. Hams, the Chinese ones mentioned for example, do up to 4 watts output. Also, FRS frequencies are in the UHF section of the spectrum, and those frequencies are generally better at penetrating buildings and such. VHF frequencies (MURS, 2m, etc.) are generally better and outside, curve-of-the-earth comms. A simple Baofeng operating on VHF freqs would most likely have a much better range than FRS. That doesn't mean it'll be great, or even enough. A longer antenna does make a big difference. The higher you can get the transmission, the farther it'll go.
I understand that in scenarios where you can be at a higher point then the Ham will go further but try it yourself.
Tune in to 462.5625 and channel 1 of your FRS and send back and forth until out of range. I've tried it 5 times or so in different areas and they both fall out of range equally.