Alex Tuch had one goal and two assists, and Stone, Tomas Nosek and Paul Stastny each had a goal and an assist for the Golden Knights (38-26-5).
Vegas is eight points behind the Calgary Flames for second place in the Pacific Division and eight points ahead of the fourth-place Arizona Coyotes.
"Every night we are tough to beat so we have to keep this rolling and see where it takes us," Fleury said.
Brock Boeser and Bo Horvat scored, and Alex Biega had two assists for the Canucks (28-32-9), who are 2-6-2 in the past 10 games and nine points behind the Minnesota Wild for the second wild card into the Stanley Cup Playoffs from the Western Conference.
Jacob Markstrom allowed five goals on 16 shots and was pulled in the first period. Thatcher Demko made 16 saves in relief.
"It's a frustrating one for us as a group and for me," Markstrom said. "When the hockey game starts you try to be focused and you try to be dialed in. Pretty much every other puck found a way into the net and that can't happen."
Tuch made it 2-0 at 5:03 when Jon Merrill's point shot bounced in off him at the side of the net, and Cody Eakin made it 3-0 at 8:33 on a rebound off Nosek's jam play at the side of the net.
"We weren't tough on their skilled guys down low," Biega said. "As a unit, we have to do better."
Boeser scored on a deflection in the slot at 10:58 to cut the lead to 3-1, but Nosek, back in the lineup after three games as a healthy scratch, scored 54 seconds later with a similar tip for a 4-1 lead at 11:52.
"It was a great response," Golden Knights coach Gerard Gallant said. "Nosek played really well, scored a nice goal and I thought the line played really well tonight so it's good to see from them."
Stastny scored on a rush into the high slot to extend the lead to 5-1 at 14:17.
"Guys came out very strong and got a lot of nice goals in the first and put the game away a bit," Fleury said.
Horvat scored on a shot off the rush 3:56 into the second period to make it 5-2 for his first point in six games. But Nate Schmidt scored on a point shot that deflected in off a defender for a 6-2 lead at 4:56.
"Every time we had a good shift they came back even stronger," Canucks forward Antoine Roussel said.