The article below is a good example of the reasoning most people will use for  taking the subdermal chip.
That main reason is Convenience ... something this age worships.

Yet Our Lord asks: What will a man give in exchange for his soul ? Mark 8:37

Bio-Bots
With a credit/debit chip in your phone (something you have) and
an RFID chip injected into your finger (something you are) you're covered!
 

Why would you not want to use this since it'll be cheaper and easier than having to carry around (and possibly forget) a national ID card or a wallet full of credit, membership, and other cards.

You may have to accept being trackable, and be scanned constantly,
but if it makes everyday life easier and more affordable - why not?
http://www.finextra.com/fullfeature.asp?id=606
 

Chip Index  www.cybertime.net/~ajgood/chipindex.html