I'm a non-triathele, and buy grease for the bearings (non-sealed hubs, bottom bracket and fork) and for lubing cables inside of the housing.
I get it in 1 lb tubs from the local auto supply store. It takes about a decade to go through a tub at the rate I use it. We're talking like $3 or 4 for a pound of grease.
There's a dizzying choice of greases available, and some are lithium and some are molybdenum-based. Some are more stable at high temperatures, like 350'F, which doesn't seem to apply to bikes much. I generally just get some general use grease in what looks like the prettiest tub, not knowing much else to use to differentiate one from the other.
Any real difference between Moly vs. Lithium grease?
Does it matter for a non Lance Armstrong?