Yup,
Taipei City and few surrounding areas in NTC are in the midst of a
HUGE 
property bubble. The mainland is in a similar situation, except about 100 times larger. Most people in this world see gold and real estate as the only
safe investments because the former will always be worth something, and the latter at least gives you a place to sleep. As MM pointed out, this phenomenon you point out is no different here in Taipei.
I too came from CA, and in SF where I was, the rents were high, but the mortgages where even higher! Bottom line: buying property in Taipei (or SF) is a TERRIBLE investment. But, if this is where you live, and you need a home to spend your life in, then buying here is not necessarily a bad thing.
Starting a 'when will the bubble burst' debate can be frivolous though because most of us are familiar with the US bubble that burst in 2008, but this one is different. The bubble here is a result of actual wealth placement, not a calamity of 'No Money Down' loans and unthinkable leveraging by the banks.