No need to survey this. Everyone would like to reduce their electricity bill. The question is that whether the would do something illegal or not

As far as I know, domestic customer is charged by real power usage and there is no penalty on low phase factor like the industrial electrical tariff. So, it does not matter if the phase is not optimized or not, the power usage would still be the same. It will affect how efficient motor is running only.

I'm sure the device contains only capacitor to correct the phase especially the inductive load. However, the home appliances that has 5 star rating already has built-in capacitor to correct phase shift between voltage and the current.