My work computer actually has McAfee on it, which I've disabled through the registry. Don't like how slow it makes my computer.
Education, people! It's better than buying useless feel-good software.
A cold virus's best strategy, for example, is to keep you awake coughing so your immune system is weak, make you sneeze and cough and have a runny nose so you spread germs, etc. But it shouldn't kill you, especially not before you pass it on. I've heard (did I read it in Guns, Germs and Steel?) that syphillis used to be more deadly, but that it got milder as an adaptive strategy.
Likewise, computer viruses probably have a pain threshold they shouldn't pass. If they can do their masters' bidding without hacking you off so bad that you format the computer, they'll be more successful.
Possibly unwarranted conclusion: computer viruses are now widespread precisely because they're Not That Bad.
So, are they worse than antivirus software? A lot of non-geeks may be asking themselves that question today. "Dang, we got a virus one time, but it didn't keep the computer from BOOTing!"
McAfee has just demonstrated a computer autoimmune disease.
As far as whether viruses or antivirus software are worse to deal with -- well, I have three systems in the shop so far today for virus infections that were so bad that it rendered the computer unusable. One woman told me she broke down and cried because her brand new laptop got infected yesterday and quit working just before she was supposed to do online college course work.
Running without A/V software is exceptionally stupid at this point, even if you think you're smarter than everyone else.
And I never run anti-virus software. At home I have Windows, OS X and Linux boxen and not in 20 years have I had a computer virus.
It's really all about usage patterns more than anything else.