I was huge into cards growing up - I had tens of thousands from 70s - 90s, all sports. I was fortunate and sold them just as ebay was starting out...I paid for my wife's engagement ring, wedding ring, honeymoon and part of our wedding for the money I made on ebay from the cards. I have since switched to signed memorabilia, but I still follow the "card industry" because my now 9-year is really into them. We go to card shows and actually went to a card shop today (more on that below). Anyway, ebay started out as good for the card industry, but it ended up killing the value of cards from the 80s - mid-2000's. The values absolutely plummeted in large part because of ebay. They became a complete commodity...ebay also killed card shows and card shops that used to be so big in the 80s and 90s. Both card shows and shops still exist, but nothing like they were. Today my son purchased complete sets (still sealed) of 1991 Topps Baseball, 1991 Score Baseball, 1992 Fleer Basketball and 1992 Fleer Baseball for $10 total. Back in the early 1990s, each of these sealed seats would have been $25-$30. That much devaluation is incredible.
Memorabilia shops (such as Fan HQ in the Twin Cities) are much more popular now.
Sadly, two of the last few remaining card shops in the Twin Cities were each victims of a professional heist over the past few weeks. A newer store in downtown Hopkins was ripped off of more than $100,000 merchandise just last month. My son and I were at this card shop today and talked to the store owners...just a sad deal. They have insurance, but won't recover a fraction of what they lost - truly a lifetime of work wiped out in a single night. A store in New Hope was also robbed a week later.
Here are a couple of news stories. I hope they can catch the scum that did this:
http://www.fox9.com/news/249170476-story
http://www.kare11.com/news/crime/thieves-hit-sports-memorabilia-shop/432253461
Go Gophers!!