Like other things mentioned with regards to Jolla, just repeating it ad nauseum does not make it true.

"Scam" implies an intention. There is no evidence of the intention of not delivering the tablets. In this regard the Jolla's campaign is very different from the Ubuntu Edge one.

There is evidence that Jolla witheld information from the backers about their financial troubles that prevented them to ship the tablets but this is:
a) common (which is not to say that it is right);
b) prudent (exposing financial troubles too early would scare off customers)
c) depending on local legislature, may even be the only legal way of doing things. For example, in the UK it is illegal for a company to announce "we are going to announce redundancies". The only legally permitted way is to say, "we are announcing redundancies".