[gostsamo]

If the coins are not a legal tender, having them will mean nothing. In order to enjoy them, you will have to sell them. People won't be able to sell you goods and services, because of the tax man, so you'll be able to get for them only stuff that is as unfungible as the coins themselves from people who will be able to use them for other such items. This is much worse market to be in compared to the rather liquid and accepted currencies.