Frequent flyer or Secret archives worker ?

While on Mike and My anniversary trip, an employee of the airline that we flew started a conversation with Mike and I. During this conversation Mike and I expressed our preference for this airline for several reasons. It was then that the employee asked if we were rapid rewards members,we were not. The employee encouraged us to become members so that we could get even better deals than we already had. He also stated that with just four round trip flights we could earn free flights. This sounded good and I intended to sign up upon returning home but life has happened and I never completed the task,until this morning that is. This morning,I printed off my paperless reservations for Friday mornings flight and decided to sign up for the program. Since one flight has already passed, I needed to call a representative for help. Having our confirmation numbers from the old flights ,I thought I was set. Not the case I soon found out. The lady who started as sweet as pie was frustrated by the end for a few reasons. One was that since we payed with gift cards( which we purchased at Giant Eagle and received enough fuel perks to fill my tank for free for)each person had their own reservation number. This was their companies rules probably in an attempt to stop people from doing this I assume. Anyway, as she got more frustrated, she asked more questions that I didn't have an answer too. There was a point where I was trying to remember if I ate peanuts or pretzels as I was sure that this was her next question. Anyway I am now told that we are registered but am afraid to check .The one question that I keep asking myself is....... Why didn't they sign me up months ago when I booked the first flight? Is this honestly a secret society that one only gets into if a company employee selects them to talk to ? In all reality, we are not wealthy enough to fly four times a year so we have little chance to earn a free flight but..... I do follow flight deals for several people so just maybe it will be worth it.