I was preparing a response but eWizzard asnwered faster.
Here's a small comparative table with numbers taken from imdb directly:
| Title | IMDB vote # | IMDB rating | Budget (USD) | Gross (USD) |
|-----------------------+-------------+-------------+--------------+---------------|
| The Illusionist | 157,294 | 7.6 | 16,000,000 | 84,276,175 |
| Mary and Max | 45,002 | 8.2 | 8,706,384 | ?? |
| Marygold hotel | 15,507 | 7.3 | 10,000,000 | 44,471,606 |
| Hotel Rwanda | 140,707 | 8.2 | 17,500,000 | 33,882,243 |
| Schindler's list | 418,582 | 8.9 | 25,000,000 | 321,306,305 |
|-----------------------+-------------+-------------+--------------+---------------|
| The dictator | 45,847 | 6.7 | 65,000,000 | - |
| Avatar | 470,400 | 8.0 | 237,000,000 | 2,782,275,172 |
| Ted | 44,314 | 7.7 | 50,000,000 | - |
| The Dark Knight Rises | 257,843 | 8.9 | 250,000,000 | - |
|-----------------------+-------------+-------------+--------------+---------------|
Not only do the "niche" movies attract more votes in imdb, but they have million dollar budgets, the biggest part of which is to attract mainstream cast and crew.
Their success is enormous (you can see the commercial gross) and they entered the history of cinema forever.
