Here’s a real world demonstration from my home, not from a video display. Some of our windows have external pull-down blinds made of a beige shade cloth. This is a fine weave, somewhat like flywire. The pattern shown is made by looking through both the regular fly screen on the window and the shade cloth. Interference patterns are caused, generating those swirly broader lines. As the breeze blows, these shift and curl and warp, they broaden and narrow, they alter from straight to curved and back again.
You often see moire patterns in the real world. Where you don’t want to see them is on your TV display, generated by accident.