Apparently this has been going on for a long time, and done by all parties, including those in power. They hold fundraisers which, by osmosis, provide guests the opportunity to lobby the party in power. 

What is the role of the Lobbying Act here? Aren't those who lobby the government supposed to be registered lobbyests? 

This is from the Commissioner of Lobbying of Canada:

"The Lobbying Act is based on the premise that lobbying is legitimate when conducted in an open and transparent manner.

The Registry of Lobbyists is the primary disclosure tool and source of information on who is lobbying federal public office holders and about which topics. The Registry plays a key role in fostering the transparency and accountability of government decision-making. Since I became Commissioner, my Office has improved and refined the Registry, making it easier for lobbyists to use and for Canadians to find information on lobbying."