Corporate Welfare Bum Meaning

Example : 1983 April 29, "End welfare dithering," Montreal Gazette (Canada), p. B-2 (retrieved 9 Nov 2015):  [A]nother $8 million went to keep alive Quebecair, a corporate welfare bum if ever there was one.2011, Cory Doctorow, Context, ISBN 9781616960780, p. 113 (Google preview):  Meanwhile: every telecomm company is as big a corporate welfare bum as you could ask for.2015 May 11, David Booth, "The Tesla secret Elon Musk doesn’t want you to know," Driving (Canada) (retrieved 9 Nov 2015):  Elon Musk . . . is also — and this you read less about — a serial, almost kleptomaniacal, corporate welfare bum whose greatest talent seems to be sucking at the U.S. government’s teat for personal gain and glory.2015 Nov. 4, Ezra Levant, "Liberal conundrum: Side with their anti-airport Toronto MPs? Or “corporate welfare bum” Bombardier?," ezralevant.com (Canada), (retrieved 9 Nov 2015):  Corporate welfare bum Bombardier is already demanding a billion more dollars in corporate bailouts from Trudeau’s Liberals.