Upper peninsula (MQT area) bolting ethics

Visited the Marquette area several times to see family and get out to climb as a plus. Found some good trad few and far between. When it came to sport climbing I noticed TR'ing is very common practice instead of leading. Why are routes not bolted (where they are needed). Maybe people don't enjoy leading? Bolt ban? No one has a drill?

Two reasons- #1 and more importantly is that almost all of the climbing areas are on private land and #2 is that there are only a couple of route developers in the area.