More and more surgeons are selecting patients carefully for surgery. Studies now show there are risk factors that predict an increased rate of complications and even surgical failure.
The surgeon has your best interests in mind. You don't want to spend that much money or time on something that isn't going to work or will leave you worse off than before the operation. Excess bleeding, poor wound healing, and fractures are just a small list of problems caused by the use of nicotine.
The type of surgery you are describing is well-known for its main complication: delayed or even nonunion of the bone. Delayed union is seen on X-rays as a lack of the bridging callous (bone) forming. This type of presentation three months after surgery is a sign of surgical failure. Tobacco use is linked with delayed union.
The longer it takes the bone to heal fully, the more restrictions there are on how much weight you can put on the leg. Without full weight-bearing, your gait is off-balance. This puts you at risk for other problems like falls, muscle weakness, and tendon shortening.
You can probably find another clinic where the nicotine restriction isn't in effect. But the best medical practice with your welfare in mind should encourage you to quit smoking before having this operation.