Buy em ep! lmao...IMO, even though there may be four million of every card, how many of those have been messed up, thrown away by people disgusted by their valuelessness, or cards ruined sitting in storage units out in the heat for years and years? I know there is still a lot out there but I know a lot of people who have just thrown this stuff away or given it to kids who practically ruin it because it's pretty much worthless. Eventually, it'll get hard to find in nice condition at the very least.
Think about a set like 93 fleer or any of the stadium club cards from 91, 92, or 93. Those things stick together in packs badly now. Not to mention they are mostly found being sold by sellers out at flea markets and such who've had this stuff in their garage or storage units forever. The cards are ruined. Stuck together like cardboard bricks.
The general value of these cards and the conditions they are kept in is an enemy that may increase their value.