There are basically few ways of getting oil out of fabrics
Using moderate to high pH (think sodium hydroxide (lye), sodium metasilicate, washing soda, phosphates, etc...
That and or using emulsifiers such as soaps along with solvents such as types of alcohols.
http://www.cleantool.org/teilereinigung/reiniger/alkohole/?lang=en
In the old says commercial laundries and others could purchase soaps built with benzene. That or people simply bought the stuff straight to use with laundry as a spot treatment and or in the wash. Other extreme was to add gasoline or kerosene to the wash tub.
Mr. Fels solved this issue by finding a way to build naptha (Stoddard solvent) into a soap in such a way it wouldn't evaporate and thus remain shelf stable. This spawned a host of copycat "naptha" soaps.
Am here to tell you Fels naptha soap of old (the one with naptha/Stoddard solvent) will remove all sorts of oil/fat stains from fabrics. This along with lipstick, makeup, etc....
If you examine the ingredient list of modern emulsifiers for commercial laundries most contain soaps, and some sort of alcohol (butyl being common) or alcohols.
Commercial laundries faced with items badly soiled by oils/fats (such as candle wax) will first launder in water (dry cleaning can set certain stains due to the heat), dry, then dry clean the article. Solvents used in the latter process are normally more than enough to remove whatever fats/oils remaining in fabrics.