The question was, why don't crows like owls. Because owls like crows, for breakfast, lunch, or dinner. Owls like the young tender ones most. Owls and hawks will take eggs and young crows from nests.
Crows defend themselves from raptors by persistent hazing called mobbing. One crow spots the perching enemy, raises the alarm with loud calls, organizing other crows with hearing distance. The crows call and call, and fly buzz-by attacks until they exhaust the patience of the enemy, driving it to flee.
Owls can take a lot of harassment before succumbing to the noise and bother. The owls in the photos, one in flight, the other about to fly, gave up, and escaped to what we presume they considered better cover.
Looking for the reason crows are raising a clamor is a good way to find owls. The owls usually are tucked back in the thickness of tree branches, often near the trunk. Hawks and owls are usually engaged in flight pursuit.
Hawks easily could kill a crow if the pest could be caught. Crows are slippery flyers, hard to catch, though, probably not worth the effort. Hawks will roll so talons present a threat to closely following crows, but a threat is not the same as capture.
Flight away from the crows' home territory usually causes the crows to abandon the chase. At that point the crows have achieved their goal — remove the threat.
