Leaking oil

I have a 1999 Subaru Legacy Outback hatchback with 120k miles. It is leaking oil, bad enough to leave a spots on my driveway, as well as it drips on the skid plate, heats up, and smokes and stinks. The strange thing is the oil level doesn’t seam to go down. The garage says the main engine seal is bad, and it is about 8 hrs labor to repair (at least). Also, I put gas in, and I go through gas very quickly. Is there anyway gas could be leaking into the oil?

Smell the dipstick. Feel the oil. Even a small amount of gasoline will be evident and yes, gasoline can leak into the crankcase.