My Jeep Sahara Wrangler 2008 uses oil big time.?

I add almost 2 liters of oil between oil changes. There doesn't seem to be an oil leak. there is some transmission fluid that leaks but that ia another story. There doesn't seem to be smoke of any kind coming out of the exhaust. On my very first oil change the dip stick was bone dry! I didn't check the oil before that because it was brand new. I find it really anoying to keep putting oil in. There should be something wrong but my dealer says it is because i drive too much. That doesn't make sence because i still change the oil after 5000 kms. What gives?