As I said up-thread, I am not subscribing, so the compendium is meaningless to me. And even if I did subscribe, I would want a hardbound source.
It would be possible to get the cards without the mini, as there is perhaps someone who wants the minis without the cards [or who is splitting them up for individual sale].
If its simply a matter of "if it's not in a book, I don't want it", than it's pretty much the same as the online stuff they've already put up for warlocks (star pact), wizards (illusionist), dragonborn ecology, and other things that were available before the pay period of DDI.
Ultimately, it's up to each group players to decide what sources they will allow. In one of my groups we are sticking to PHB only for the first adventure anyway, to get a feel for the stuff in there before allowing other stuff.
Conversely, I'm running a game with a drow rogue running around with a double sword, and a warlock with dark pact powers, each of which has feats from their respective online articles, and there is likely going to be a barbarian joining the group soon.
The existance of the cards you don't want to buy/use isn't any different than the existance of the powers/monsters/feats/paragon paths/epic destinies offered through Dragon and Dungeon ... in fact, the cards are at least a hard copy vs. a pdf only that you need to print out to get a hard copy.