As rockets get larger, the importance of drag relative to mass decreases (drag runs generally proportional to cross section and surface area while mass runs generally proportional to volume). Hence big rockets tend to have less pointy payload fairings, which provide more useful volume by mass, as Hobbes' answer shows.
Qu8k was a small rocket developed with the sole goal of reaching 100,000 feet (30km) altitude under the Carmack Micro Prize rules; it was designed over a weekend and took some departures from normal amateur rocketry conventions in the name of reducing drag:
Most pads require use of a launch lug or rail guide. These protruding parts on a rocket create lots of drag. By removing these parts, simulations showed I was able to increase peak altitude by over 10,000 feet. The desire to keep drag low and have full control over when the pad would be setup and available for launch drove me to make my own launch tower.
The Wikipedia nose cone design article that Hobbes links mentions that conic tips are often chosen for ease of manufacture over more complex shapes, and this was probably the driving factor for Qu8k. This chart from that page shows that cones are actually poor performers in the transonic regime. Qu8k reached its top speed of around mach 2.8 at only 17,000 feet (5km), meaning that it spends a lot of time in dense air at speeds where a conic nose is not ideal:
Comparison of drag characteristics of various nose cone shapes in the transonic to low-mach regions. Rankings are: superior (1), good (2), fair (3), inferior (4).
So presumably the tradeoff here was that Deville knew he could fabricate a conic nose cone, and his simulations said it would go to 100,000 feet, so that's the route he took; I imagine that with more time and effort he could have made a very slightly smaller rocket with a Haack/von Kármán nose and reached the target altitude, but in rocket development it's very rare that you're ever optimizing for only one factor.
The chart doesn't show the performance of spherical-tip conics separately from pure conics, but I suspect that a 1cm radius tip would have been an insignificant difference on this rocket: a little more time in the shop grinding the tip down, and a little less likely to accidentally puncture something while being handled, and still capable of breaking 100,000 feet.