Which came first, the Sucker or the Con Man?

I have often reflected on a childhood memory, searching endlessly for its true meaning.
I wonder---is there any substance to these events, or was it merely a bit of childhood fun? Perhaps you can help me out... (Laura, your input will be kindly excluded, since you are not an impartial party.)
When I was a kid, let's say somewhere between 6-10 years of age, I would often walk to the corner store with my sister, who was a year and a half older than I. We usually traveled together discussing the items that we would buy with our $4 or so, the money that we had earned from chores or what have you. When we got to the store we would go our separate ways. I would look at balls, color books, toys, etc. and a little while later I would meet up with my sister, who was without fail always in the candy isle, contemplating which sweets, exactly, should be her "inventory" for the week. She would eventually pick her items and we would head home with our new treats.
As soon as we got home my sister would lock herself in our "playroom" (playroom=the room my mother had given up on and allowed us to make into a den of trinkets and toys) and would begin setting up shop. I was not allowed in. I was instructed to wait outside until further notice. I eagerly awaited the opening of my sister's makeshift store, wondering what she would come up with this time. A little later, perhaps 30 minutes or so, my sister would throw the sliding door to the playroom open, revealing a piano bench full of chocolates and sweets---all donning a rather hefty "price tag" scratched out on a piece of notebook paper with a crayon. I would scan the merchandise, pick out what exactly I wanted, then I would run frantically around the house, overturning couch cushions and rummaging through drawers searching for the necessary coins to meet her asking price. I knew I had to have the exact amount. Shopkeep Laura was a stickler for prices. And unfortunately for me, the price was usually about 50% more than it would have been if I had just bought the damn candy bar at the store myself.
So, like a frenzied junkie, I did this for days on end, searching and begging for quarters and dimes and the occasional nickel, until I had purchased each and every candy bar the Shopkeep Stickler had to offer. Then, and only then, was I truly satisfied.
If this were a one time fluke, I don't think I would be so concerned about what this could or couldn't mean. But unfortunately, it was not a one time thing. Time after time Laura peddled her stuff, and I always gave in to her tyrranous candy-selling reign. No questions. No resistance. Just silent acquiescence to her immoral and unjust enterprise.
I know this might be asking a lot-- having to delve into my psyche and perhaps ask some probing questions, but truly, I need to know. Why oh why would I do such a thing?