Here at Geeks Central average about 1 XP machine for repair every week. Why? Often the XP machine is attached to a piece of industrial equipment (i.e. a roof top air conditioner.) To upgrade the machine could cost thousands of dollars. Another scenario is an old machine that was put in storage but has all of the family photos are on that computer.
If you are still using XP, there are a couple of things to watch out for. First, be very careful when going online. XP is vulnerable to all kinds of nasty viruses, trojans and malware. Secondly, do regular hardware maintenance. This includes regular inspections and blowing the machine out from dust once a quarter.
There is no shame in using an XP machine. It still has its place in the technology world.