I got some without a '4' on purpose because it's a bad number in China.
Got some that ended in specific last two digits for personal reasons, like day of birth (didn't care what first three digits were).
Got some with first three digits that are high population area codes (514, 416, etc), didn't care about last two digits.
Hey, there were so many available at the time I had to decide somehow. The '4' being a bad number might be overrated, because outside China 4 is just another number to most people.