Until politicians are held to account for their manifesto pledges, and their performance in the job, lobbying will be a big part of politics, and shifting manifesto pledges.
Politicians can be held to account by the electorate at the ballot box.
Unfortunately much of our legislation is generated by the EU which doesn't have either a manifesto or an electorate.
Lobbying is a fact of life, to a greater or lesser extent, in all "democracies".
In the EU there are in the order of 30,000 lobbyists.
Given that they've taken years to develop a "relationship" with the relevant politicians/bureaucrats there are no prizes for guessing how many of them want the UK to remain in the EU and to maintain the status quo.
They play an active role in developing EU policy and invest billions of Euros for the privilege.
The only democratically elected body within the EU, the European Parliament, are resisting attempts to introduce transparency into the Parliament on this subject.