To date, out of 36 races that compose NASCAR's current schedule, only six tracks doesn't not see a repeat visit from NEXTEL Cup series each season: Darlington, Las Vegas, Chicagoland, Kansas, Infineon (Sear's Point) and Watkins Glen. Two of the five are road course races (Infineon and Watkins Glen). What's interesting is that a lot of fans are starting to wonder why NASCAR does not want to expand on the complexity of each venue that they visit. Some want to see the NEXTEL Cup regular revisiting thier roots on the dirt tracks. Others want to see more (or less) road course races in different places in the world. One even suggested placing them in Japanese-style "Drift" races, just to see their abilities at their limit.

Yes Sir, Mr. 14Falcons! If NASCAR started Driftin', old Sterlin Marlin would be a winnin'
What is inspiring these suggestions and complaints from the fans? There are several possible reasons. One reason is that they're seeing domination of certain types of tracks from just a handful of the same teams. Fans pick drivers for a variety of reasons. One of the many reasons they may pick a certain driver because they may be good at the 1.5 mile tracks, they may pick a short track master and maybe the love the road ringers. Regardless, each driver has a penchant for one style track over another. A great example is the now retired Rusty Wallace. He was a short track specialist from St. Louis, MO. Out of all his wins and his championship title, he's never won at a restrictor-plate track (besides his non-points Bud Shootout victory in 1998) in his illustrious career (1). What most fans are crying for is a diversity of tracks, so that many a driver would be challenged on all types of racing disciplines thoughout the entire season.

The venerable Rusty Wallace has never won a points awarding race on a restrictor-plate track in his entire career.
Another reason for the grumblings are the fact that there's a lot of NASCAR fans that live are too far away from the closest NEXTEL Cup event. Place yourself in their shoes (if you don't happen to fit the description of already). Imagine living in let's say... Montana. Where's the closest track available that NASCAR's NEXTEL Cup circuit? Kansas? Their complaints are valid ones, so what's holding up any possible implementation of new tracks or events?
The some of the reason's is simple:
1. Demography of NASCAR fans in certain regions of the country. If there's a total of a 2% return on the Nelson Ratings at a certain location of the country, what's the point of sending the circus into town?
2. The cost differential between the location's taxpayers and the company who's building the track. If they don't want to pay for it, why should you try to built it (Washington State).
3. Seasonal weather patterns. Although it would look cool... NASCAR on ice, it wouldn't be much of a race in Anchorage, Alaska in late November.
A third reason to why NASCAR doesn't expand on their venues is because of past, current and pending lawsuits against them. The reason why NASCAR lost one of it's historical and celebrated races, the Southern 500 at Darlington, was because of Bruton Smith (owner of Speedway Motorsports Inc.) vs. NASCAR lawsuit (2) . Another current lawsuit pits the Kentucky Speedway, which is a favorite track for testing by NEXTEL Cup teams (3). All these stem from an ongoing fight to secure one or several dates on NASCAR's schedule.

Bruton Smith... everyone's favorite (eccentric) Grandpa!
Although it would be next to impossible to see them come true, most of us still dream of a diversified schedule. With the monotony of the "cookie-cutter" ovals and lack of a real driver challenge to them, it's no wonder why the world looks down upon our sport as second-rate. Yes Sir and Ma'am, I'd love to see it myself. I'd love to see Tony Stewart win at Monaco, but I guess that we're stuck with what we've got... for now.
Sources: (1) http://en.wikipedia.org/wiki/Rusty_Wallace
(2) http://www.jayski.com/pages/tracks/lawsuit.htm#texas
(3) http://www.jayski.com/pages/tracks/lawsuit.htm#kentucky