Raonic became the tournament's first three-times winner since Tony Trabert (1953-55) and said it was a pity he would not have a chance to chalk up another win at the event, which dates back to 1889 and is being dropped from the ATP schedule.
"I'm really sad to see it go," Raonic said. "It was a got-to part of my schedule and it's really unfortunate I won't get the chance to play it again."
Raonic, who has only been broken twice in 12 match wins in the past three years, nailed 19 aces and never faced a break point.
The 34-year-old Haas could never get into his service games, while Raonic broke the German three times. The 22-year-old Raonic also fired in a 148mph (238kph) ace.
"If he plays like that consistently, on this type of surface, in this arena, take anybody at the top of the world and I would say he's got a shot at beating them," Haas said.
"He played extremely well. He placement on the serve was extremely good. His speed and power at times ... especially on that surface, where it kind of skids and goes through, it's really tough to try to control and get it back.
"I didn't play a bad match, I just came up against a guy who played some unbelievable tennis."
Raonic, who won his fourth overall title, said he had improved so much since winning the 2011 title.
"I'm a much better player in general and a better competitor and I have more experience in knowing how to deal with situations," he said.
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