That seems to happen frequently. But they don't seem to mind.
Raptors come in all different sizes now, from falcons to eagles. It's possible the same avian characteristics we see in the larger dinos was similar in pattern to various sizes as needed for the environment.
For as much as we know, there is a whole lot more yet to discover.
Something doesn't sound right here. I'm a little over 6 feet and weigh around 200 pounds.