My sister and her daughter (my 19 year old niece) have a serious beanie babies collection that they insist is worth some serious money. Back when the niece was perhaps 6 or 7 and my boys were very young my mother gave each of the grandchildren a BB (beanie baby, not a gun) and my sister nearly had a heart attack when I pulled the tags off (a serious no-no for a collector) and yelled at me "Do you know how much those are worth with the tags on??!! You just ruined their value!!!" And I responded with "They are worth exactly as much as smiles the boy's faces. Perceived value means nothing compared to that in my mind."
She could not grasp the fact that they are only "worth" what somebody was willing to pay for them. Kind of like gun collectors who insist on collecting guns that have never been fired. I never got that mindset.