Park employee: we've received complaints that your flag snapping, Could you consider taking it down.
$hit-stirrer: YOU CAN'T TELL ME WHAT TO DO WITH MY FLAG.
GOP echo chamber: We are oppressing Patriots.
Reactionaries: Put flags on my truck (violating the flag code, again) to support patriots.
If they're paying you, they get to establish boundaries. You don't like the boundaries, quit. Someone else without a raging hard on for jingoist displays in the work place will do the job, instead.
reality: Flags in high winds sound like gunshots and we're disturbing everyone in the park. As a contractor doing a job, you need to be mindful of causing a disturbance. He could have taken the flag down, but got on rails about "being told what to do."