Using wikipedia to expand our vocabulary...
Silicone grease is a waterproof grease made by combining a silicone oil with a thickener. Most commonly, the silicone oil is polydimethylsiloxane and the thickener is amorphous fumed silica. Using this formulation, silicone grease is a translucent white viscous paste, with exact properties dependent on the type and proportion of the components.
The word "silicone" is nowhere in sight...
And here I thought it was merely slimy stuff in a tube.
The last time I purchased silicone grease it came in an aerosol can. Perhaps you were on the wrong isle?