My parents didn't have jobs that allowed them to travel for work, but travel was always a huge part of our family growing up. We took at least one "big" trip a year, and several small weekend trips. They signed us kids up for all the FF accounts, and thus I still have my old TWA cards! I remember staying at the Ritz Carlton in St. Louis one year for a dance competition, and it was by far the nicest hotel we ever stayed in. My mom had gotten a great AAA deal, so we lived like kings for the week. They did the timeshare presos for *wood, Marriott, etc. and we got free weeks at Disney. In my teens, I began to realize that a discount can be found if you look for it.
In college I was gifted EXP status on AA by a close friend, since I was doing a lot of transcon flights. I moved to Atlanta for my first job, which required travel almost every week. And then the Delta obsession started. So far it's been 3 years of M-R travel every week, and I've slowly moved from FO, to GM, to DM this year. I haven't paid for a vacation in that time, and have seen some fabulous things. I've been able to send my parents on a last minute Super Bowl trip, to spring training, and a family trip to Disney with my 5 yo niece. I generally don't go out of my way to earn more miles/points, but I will maximize what I can. No MR's, etc. - I spend way too much time on the road as it is, and I haven't had a problem earning top tier with my normal travel patterns. However, there's always the "I just need a few more points for x trip!"