Except if any of your pages are cached between eyeball and your server and so your server logs don't capture everything that is going on. You can get fancy with web server logs, but depending on what you're trying to understand it may not be the data you need.
<source: did fancy things with logs over the last 25 years, including running multiple tools on the same site in parallel to do comparisons (Analog, AWStats Urchin, GA, Omniture, homegrown, etc...)>
If you control the cache layer, log it there. If you don't control the cache layer, does a read from the end user cache really count as a separate visit anyway?
There are plenty of situations where someone visiting a page once and someone repeatedly looking at that page over a period of days (even if it is pulled from their browser cache) is an important difference. Obviously it depends on what you're using the data to try to understand.
<source: did fancy things with logs over the last 25 years, including running multiple tools on the same site in parallel to do comparisons (Analog, AWStats Urchin, GA, Omniture, homegrown, etc...)>