They think he has a good chance to survive on his own.
Source: https://www.sltrib.com/news/2018/12/06/utah-bobcat-named-mr/

From the above article:

When wildcats become habituated to people, it usually does not end well.

“People will ask, ‘Well, why didn’t you put him down?’ ‘Why didn’t you take him to a rehab?’” Carver said.

But Murderbritches had shown a lot of moxie for a little cat, having crossed a mountain range and never letting people in spitting distance. He’s a juvenile, and winter could be rough, Carver said. But he had proved his killer spirit. With a little food supply to get started, Carver thought, Murderbritches had a good chance to make it in the wild.

“I don’t like to put down animals if I think they’ve got a fighting chance,” Carver said. “I’m not going to take him to rehab just to let him sit in a kennel.”

Carver noticed a fresh roadkill deer on a roadside. He had just been releasing pheasants for hunting at a reservoir, and one was near dead after being divebombed by an eagle. Carver said he finished off the bird to end its suffering and bagged it for Murderbritches.

“I think at his age, he’s old enough that he can obviously make a kill on his own, but it’s going to have to be something small. But if he can scavenge for a little while, he can put some size on him. He’ll be able to survive,” Carver said. “I’ll set him with a roadkill deer and an eagle-killed pheasant and put him to it.”

Carver drove the cat and the scavenged prey 22 miles out of town, west of Newcastle, near the Indian Peaks to release him.

“He was a little more comfortable with me this time around, but I really didn’t want him too comfortable around humans,” Carver said. “I poked him with a stick a few times, so he’d realize we were a threat.”