Well, like I said before, if the company is lying then there is nothing to be done. However keep in mind that the power consumption of a fan depends on my factors. Size, pitch, angle of the blades, material used in the construction of the blades, quality of the coil, capacitors inside the fan, RPM of the fan and the air displacement of the fan. So, it is difficult to compare two fans made by different companies even if they are the same size fans. The only way to measure the true wattage probably is by calculating it yourself.
However, typically the watts mentioned on electric appliances are the maximum that appliance will ever consume. So, if your washing machine says 290 W then that means it will consume 290 W only when it is running at max speed. So, since the company says the fans consume 70 W. This has to be the rating at max speed. These fans are also exported so probably have to meet some sort of certification or something. You can get away by making false claims in Pakistan, however, in other countries you can get sued. So that was my reasoning that they should consume only 70 W. It might be that the company is selling inferior quality products in domestic market but good quality one abroad. Who knows.