Money has multiple functions, one of them is hoarding (aka saving). Even if Bitcoin had zero merchants and served this hoarding function alone it would be valuable.
Because it is:
- Decentralised
- Non-inflationary
- Easily stored and transferred
- Anonymous (sort of)
- you continue...
I would argue that in a conventional economy there is a difference between hoarding and saving.
Saving = Investment, ie savings are productively invested in the future of the economy
Hoarding = burying in the back garden (or location of choice) - this is a non-productive use of resources - and there are very few ways currently of productively investing BTC (I am not sure lending them on margin counts - and Havelock Investments and the like are not yet trusted by large sections of the community - with many valid reasons)
You are free to mess up the nomenclature of course, but:
Saving money is having the money in your possession for later use.
Investing is buying capital goods for your money with the intent to profit from it.
Lending is letting others use your savings to invest or consume while you don't need them, for a fee. This includes depositing your money in a bank.
Hoarding is a derogative word for saving. It can be used for saving money or for saving other things for the future, like food, fuel.
The purpose of having money at all is to consume, now or later.