Not necessarily. Nearly everyone knows a savvy person like us. I've installed Adblock on many computers belonging to less savvy people, people who might be inclined to click on ads.
Also, not all ads are brain dead "you're the millionth user!" type. Some (most?) are targeted to the individual. When I'm browsing with Adblock turned off I see all sorts of ads for web services that I would genuinely consider buying.
When I'm doing computer services as part of my side job, I usually install AdBlock and set the option to allow Google ads. I know there are a lot of ads out there which are great and useful and nice and I would like to be seen, but Google's are the only ones I know I can trust to not be large, resource intensive Flash ads hosting malicious exploits.
Also, not all ads are brain dead "you're the millionth user!" type. Some (most?) are targeted to the individual. When I'm browsing with Adblock turned off I see all sorts of ads for web services that I would genuinely consider buying.