Thanks to everybody that contributed.
I did go to the place and the "clerk" or whatever they call the bank worker at the counter almost looked annoyed... I told her i lost it and she seem to not care, i even had to ask her to take my name and phone number in case someone would return it.
I didn't call the cops in the end, mostly because of the small value of the item. Still piss me off to loose money, especially since i don't role on it right now. I had lots of debts to repay due to last month comiccon (borrowed money to have one hell of a trip) and i just finished paying them up and that one little thing i bough for myself was like the only thing i could afford that week :/
You guys will laugh but ill tell you what it is. An Xbox Live subscription card... My xbox live just finished and i needed a new one so i got to the video store down the steet, bough the card, and for some unknown stupid reason instead of putting it in my pocket, i kept it in my hand. When i arrived at the bank i just put it on the side thingy, and i forgot to grab it back as i got out. For the ones wondering i was taking money out of the atm to pay the debts ...
Thanksfully i didn't loose any additional money and the item lost is not something of sentimental/convenience value like sunglasses or a hat i love, as in it can be replace, its just a loss of its monetary value. Obviously ANYBODY could take it and if they don't own an xbox, they can always resell it anywhere like facebook video game groups for 90/80% of value and make a buck... I even left the video store "movies of the month" paper thing wich they also took and the invoice was thumb tack on the card... so not even the invoice to try to have it canceled or whatever.
It could be worst sure, as i did "lost" 2 times my favorite caps when i was younger, one time it was an ecko (when it was THE popular brand) that i had just paid 50$ and i was 16 so it hurted, the second time it was a Halo 3 cap i got as a pre-order bonus when the game came out. The halo one had a bit of wear and was brown instead of black due to sun so i guess it was a little less annoying but still. I even lost a Gold ring once again when i was 16. I never wear rings(at least not of value), but i was meeting my girlfriend of the time wich was in a different city and i wanted to look "cool" so i put it on. Was my grand father's ring. Its monetary value was low as the jewels on it where gone but it was the sentimental value... I removed it to wash my hands and forgot it on the counter of the bathroom at my girlfriend's school...
Obviously my girlfriend check with the secretery for the lost and found items but it never turn in... Still mad at me to this day for that one specifically.
I hate loosing money and even more my stuff. I was very piss when i realized my xbox card was gone. I spent the week without being able to play on the internet because of it as i had no money to buy another one. But i guess if i can see the positive of a negative situation, since today xbox live is free to play for everybody (i guess for the weekend) so even if now i could get a new card i can wait to enter the code and enjoy the free days... "lol"