Mr Morrison, surprise, surprise, is being somewhat disingenuous with his statement. Multinationals and for that matter Australian companies, do not pay GST they collect GST. My political cynicism tells me that by using the words multinational, pay and tax in the one sentence he thinks that he can bluff the populace into thinking the government is doing something about the income tax that they are not paying.
As someone else noted, I don't think that Australians really begrudge paying 10% GST. I do think however that we have an issue with some of the extortionate mark-ups applied locally.