Wow. I just turned 27, and I have NEVER gotten that question. No one in my social circle is married--there are a few engaged couples, but they have been together FOREVER, and it was about freaking time!
Perhaps it's urban vs. non-urban/coastal vs. flyover or something like that. I know a few people from college who have gotten married, but they either were together forever or got married quickly for religious/social reasons.
At 27, my 10-year HS reunion is coming up, and most of the people who got married within 5 years of graduation are now DIVORCED. Who wants to be divorced at 23?