I don't think so, no. You're purchasing a license to use the software, not the software itself. You have a valid license, it shouldn't matter where the media comes from. Adobe used to sell just the media itself for about $5 + postage (basically to cover the cost of the floppy disks.)

They're not losing money by you downloading old software, especially software that you've already purchased a license for. So long as YOU are not the one enabling other people to infringe on copyright, I think it's fine. Then again, I'm not a lawyer.