[thisisit]

Oh, but they can. Here's what this whole drama has proven:

Any one can fork a coin. Then attach a significant market value to the given fork by promoting it heavily. Or if required they can do it after the fact - They can be on the buy-side and creating an ever increasing bid to pump the fork.

As for the support, you will have human greed play a big role. Everyone holding x coin gets 1 x coin + 1 fork coin with significant value which means it will create some market as well as intice miners to mine a coin with much smaller difficulty.