These are clearly not the same motors... These are just comparisons with charts and data range that do not make much sense.. True difference between the motors are seen in their effiency and at higher power levels. Better (and more expensive) motors with higher tolerances and better materials have better effiency. Smaller or cheaper motors have their effiency curves go up and down more earlier and therefore at lower power Turnigy is close to Hacker.
In other words smaller gaps (between stator and bell), better magnets and copper produce better effiency (but cost more to make..). Motors also have different bell design and Hacker's design looks to me like it's acting as fan too, which cools the motor when run longer periods which also improves the effiency on longer runs.
If you look at DrMotors measurements the "right way" you'll see that the Hacker has higher effiency at whole range. Higher effiency produces more power and less heat at same input power. Heat usually breaks the motors, so higher effiency motors produce more power per watt AND can take more input watts (without breaking up).
With biggest props (Highest watts) Hacker's effiency is at 71.9 % and Turnigy at mere 61,1%. That means that Turnigy produces over 30 % more heat at these levels (28.1 % vs 38,9 % of input power goes to heat the motor). Simply put, the Hacker can give more than 30 % more power out without breaking. Usually better (more expensive) motors use better materials which can resist more heat and have better design (airflow), so the difference might be even bigger.
DrMotors price comparison is on the wrong track as he is comparing prices in China without taxes and custom duties to local prices in EU with tax and custom duties included. To these chinese prices one needs to add shipping, custom duty and local VAT. Hacker is still more expensive, but it is also much better motor, so you get what you pay for.
These motors might even come from the same factory, but that doesn't matter as the factories make what the customer orders. If you order a 30 usd motor, they will make you a 30 usd motor. First question when designing a new product with a factory is the target price.. Same factories make different quality and different price range motors.
Here is a chart from DrMotors results with effiency / power.
