I was fortunate enough to have had both parents in the airline industry (although mom quit when I was born), so I have always had plenty of free flights.

I am probably a bit extreme example 'cos dad was posted in England and Australia while I was growing up and I wound up commuting between there and home (India) for school to the extent that I logged my first million miles by age 15, all without spending a single dime on airfare. I was 18 and in college before I even travelled on a paid ticket for the first time.

Even now, in my late 20s with dad retired, I still get a fairly decent (albeit much more limited) range of free and rebated flights both with his carrier and with other partner airlines. Since dad retired as senior management, he keeps his benefits for his lifetime and entitles him to space-available Business Class travel systemwide on his airline.

Most airlines are generous with travel benefits, but it should be noted that with VERY few exceptions these are purely space available. I've lost track of the number of times I've either been shoehorned into the last middle seat between two fat, smelly folks or worse still, left behind. You can get Positive Space passes but those are usually for exceptional cases like family emergencies, service anniversaries, awards, etc...