That Time I Got A Pair of Jeans for Free

First of all, I generally consider myself to be an honest and decent member of society (mostly). However, I also feel you get mocked and screwed in life a lot - sadly, especially as a good person. I know it sounds pessimistic, and probably it is, but I feel like selfish, egotistical people get further in life and, sadly, often on the cost of the good, decent people. But I am digressing here, actually I wanted to talk about something nice that happened to me lately and although it is actually a bad thing (as it comes technically close to stealing), I couldn’t help feeling great about it.
Recently, I went shopping and I don’t mean buying the odd thing here or there, but I actually went shopping with quite a bit of money and bought a couple of unnecessary items for spring (like shoes and a jacket). Anyway, I was in the Mango store of the DEZ’ shopping centre in Innsbruck and bought a pair of jeans and a white-and-grey striped jumper there (they look fantastic together). So, I only bought two items and they were 20 Euros each, so 40 in total – if there hadn’t been the lucky (or unlucky – let your morals figure that out for you) incident.
When I left the shop, I realised that I had only paid 20 Euros for the two pieces and when I checked the receipt, I saw the sales woman hadn’t typed in the pair of jeans – so I had got it for free!
This is funny because I had had some issues with the jeans in the changing rooms beforehand. I HATE buying jeans, but among the usual reasons why people hate buying them, there is the additional reason of my stomach condition which makes me puke if I wear jeans too tightly. Then, on the other hand, I don’t want to look saggy with a pair too big-sized. So I was in there with two sizes, one my size and one a size bigger. I decided, against all the odds, to take the smaller one and now that I didn’t have the jeans on the receipt I couldn’t return it anymore if I wanted; however, as it was for free, it wouldn’t have mattered if it had been too tight anyway (it fits perfectly, by the way, in case you were wondering).
But now to the dilemma...should I have returned and told the sales woman? Probably yes, after all, I felt so guilty about it when telling my friends and my man that I actually lied to them, saying I had only noticed when I had already left the shopping centre (sorry you had to find out this way, people). Still, when I realised I had got through with the situation, I felt a wave of joy and satisfaction sweeping my body (is that a bad sign?), as for once I was the one who had screwed somebody (even if only unintentionally) and not the other way around. Besides, the sales woman was talking constantly to another woman while she was supposed to serve me and, honestly, if you’re too dumb to keep track of two pieces, it’s on you.
Either way you see it, I am now sitting in my new pair of jeans and have to smile a little every time my eyes graze them as having them got for free although I shouldn’t have gives them extra value, somehow, if you understand what I mean...