Even for the home power user, it's a pain if you are forced to buy brick and mortar and on a deadline because the family needs a new machine. Old-style PCI has become a pain to find on cheap towers.
I had to shelf a bunch of cards when our old ~2003 machine died 2 years ago:
- an old $120 PCI video card (the cheapest replacement costs ~$60 these days)
- a Soundblaster card (I miss when they used to have MIDI and joypad ports)
- a potentially secondary NIC that would have helped me play around with work multi-nic setups and software firewalls
- an adapter card for 3 Firewire inputs.
- a modem card (didn't get more than a couple uses after we went to DSL, but can save you a dollar and a trip to the Western Union when your potential new boss requires documents faxed before you're hired)
An old system I used to maintain had 2 native USB port and about 4 more via a PCI card I added. I think my switch from the hand-me down ISA to my self-bought PCI setup had only 1 card that got dumped. We just have so many more gadgets today.