But honestly, if a company says I have 6 GB of email space, I'd damn well better be able to use it, regardless of how many other users are using it.
If an ISP says I have a 10 MBit connection, and unlimited bandwidth, I'd better be able to use it to it's full capacity 24/7 regardless of how many other people are using theirs.
I say a company should be able to deliver everything they promise to every individual at any given time, regardless of how many others they are serving at the same time.
If I'm paying for a 10 MBit connection and unlimited bandwidth, I should get exactly that. Not a connection that mysteriously gets cut in half when everyone else is online.
I should also mention that if you are doing something that requires a heavy duty server, with customized hardware, good luck fidning anything that will fit your needs for cheap. For example, if I need a server to run a dedicated WoW server for say, 1000 people at once, I'd need a fairly beefy machine, and a fairly beefy internet connection. Would one of those cheap hosting sites be able to provide a system capable of running that and not sucking ass? not bloody likely. How many users share a single server at solutions like veritynet.net?
If you were to own your own server and user your personal internet connection to host that server, you'd have a couple advantages: You'd be in the same location, and be able to service it yourself, you'd have less fees to pay, and you'd have the left over bandwidth of your connection to use as you wish (say you had a 20 MBit Down 10 Up connection from FiOS, you'd have most of that 20 MBit down left for your use, since you'd be uploading much more than downloading running a server). You'd be able to deal with server issues much faster than having to notify the company of the problem, get them to call someone in to repair it, wait for the guy to repair it, and then wait till you get told it's back running.
Of course, there are times when that may be a more effective way of doing things (if the repair guys have some hardware on hand to replace damaged/dead hardware and such, or if you know less than they would about how to service/troubleshoot your server), but if you are proficient at troubleshooting/repairing your own server, you can save some money by using your own highspeed connection instead of having to pay fees for the server.
Another aspect is space. Sometimes you may need a large amount of space, but not much else. It might cost quite a bit to get a service that gives you enough space, but you might also end up with a bunch of excess stuff you won't ever use. Hell, If I could get upload speeds of say, 150 KB/s, I'd be running an FTP server on this computer so I could download what I want from my computer whenever I'm somewhere else. I've got 1.4 TB or so of space, but my net is just a bit too slow to make an FTP server worth it. Looking at veritynet.net's server costs, getting 1.4 TB of hosting space with a half decent speed (say 2 MBit/s up) would add up VERY quickly. And that's on top of any home internet costs. The other aspect is that most hosting places charge you for our bandwidth. Hosting at home wouldn't because pretty much every broadband connection is unlimited. If mine wasn't, I'd owe a LOT of money. I've listened to di.fm for over 1200 minutes straight before, that's about 843 MB of music, on top of that 300+ GB I've downloaded through bit torrent, plus the god knows how much downloaded through firefox, and all the other stuff. I would SHRED any bandwidth limitations pretty damn quickly.
Though I will admit that veritynet.net has a pretty decent price range, compared to some stuff I've seen online, it's definitely not cheap to run a half decently sized server.