Memories for Sale - How Much are Yours Worth?

Photo Credit Jeneill De Jesus

The other day my trip to Curiosities with Jeneill reminded me of a fascination I have with old photos. I first noticed the baskets and bowls and drawers and piles of old photos, postcards, and personal letters for sale atUncommon Objects. I'm sure they're everywhere, but the ubiquity of them at Uncommon Objects caught my attention.
I kept having the urge to buy some, but every time I started to flip through them I would stop and wonder why I would want these. Doesn't it seem a little odd (perhaps almost morbid) to purchase something as personal as family photos or letters when you know nothing about the people in them or the context in which they were created? I know this would probably be an anthropologists dream, to just horde  these things and examine them. But alas, I am not an anthropologist.
Part of me completely romanticizes the entire endeavor by reasoning that I would buy these photos and ponder the lives of the people in them, creating a new past, present, & future on their behalf. I can bestow my own sentimental value upon them. The other part of me thinks that only the loneliest people would want to surround themselves by strangers.
Then I wonder how the subjects of the photographs would feel. Knowing that the memories of them have been abandoned, perhaps unwittingly or unwillingly. Knowing they are forever anonymous. And how does one put a price on these things? To say that you shouldn't buy them is like saying they're worthless, yet how can you give it value if you know nothing about it?
How much is a memory worth? Is there any value in a paper relic of another person's past if you don't know anything about it? SHOULD I BUY THESE OLD PICTURES?