The cheaper price is because you are signing up for a 2-year contract with a phone company so they’re subsidising your phone. There’s actually nothing discriminatory about that. If Taiwanese want to simply upgrade their phones and keep their old accounts they have to pay the higher price too. What is a bit discriminatory is that (I think) they don’t let foreigners get an account anymore (and so take advantage fo the low prices) unless they have a guarantor.
Bri