It's simple. There are less 7 drivers than there are 1s, 3s, 5s, and Xs owners. Only a small number of 7 owners are actually on forums (maybe due average income/age of owners). Out of those 7 owners, a few will modify their cars or need help with DYI. 7 owners probably can pay others to do any work.
Only a few select breed of us 7 owners like to get our hands dirty and are car nuts. Just my theory.
