I don't think I'm a purist by any means but I really hate playing on brown grass. I took advantage of the free golf survey deal at GlenEagles last year and froze my nards off one weekend, in addition to playing on pool table fairways. I recall hitting off a lot of teebox mats too...
I love golf as much as the next duffer but I just don't bother until the grass is green and it's at least 12 degrees. Quite frankly, range time would be better for me to shake off that rust than a round on the ground... (uhhh yeah.... "shake off"...like it comes off......)