There's another reason. Hobsbawm clearly has a passion for her profession and relishes the chance to champion good practice, berate poor performers and advocate proper training. Her current gripe is 'spin'. To her, spin is not just a piece of jargon invented by the media to put down PR, but a valid word to describe bad PR.
'Spin can involve lying; it's when you will do anything for your client and, in a 24-hour news climate where journalists will do anything for a story, that is a dangerous combination,' she says.
Hobsbawm's career started in publishing as a publicity assistant at Penguin and then as head of publicity at Virago. A career on the other side of the media fence followed, as a researcher for Thames TV and then the BBC's Wogan.
She spent a short time at British Satellite Broadcasting, but was made redundant when it merged with Sky in 1990. Labour Party work followed and by the early 1990s it was time for the self-confessed 'compulsive networker' to set up her own business, especially after building up contacts around the world in politics, publishing, the arts and media.
What began as Julia Hobsbawm Associates soon became HMC, after linking up with Sarah Macaulay.
Ten years on, her latest media appearances aim to publicise a change in her agency's direction. Her business partner of nine years, the Chancellor of the Exchequer's wife Sarah Brown (nee Macaulay), left last year and now works in Brunswick's arts division. Hobsbawm has bought her out for an undisclosed sum and is to relaunch under the name Hobsbawm Media + Marketing Communications.
She sees the break as a chance to impose more of her personality on the agency - notably her political side. A strategic alliance has been formed with niche lobbying agency Project Associates. Recent client wins, to join a roster featuring the likes of Saatchi & Saatchi and the Cabinet War Rooms, include the World Health Organisation and the Work Foundation.
Sally Feldman, former Radio 4 Women's Hour producer and the London College of Printing's dean of media, approves of this change in direction: 'She's a cross between (Marxist writer) Rosa Luxemburg and Edina from Absolutely Fabulous. A furious networker with a real ideological commitment.'
Hobsbawm's politics are well-documented. She's a former Labour member and head of the party's high-value fundraising arm. She still supports the party and comes from a political family - a slight understatement since her father is the renowned Marxist historian Eric Hobsbawm.
She now feels she can be of more use outside party politics, saying: 'I think I can be more engaged away from that.' One way she is 'engaged' is as a founding trustee of the Facial Surgery Research Foundation, whose research director is her cousin.
Despite dropping out of her Polytechnic of Central London degree during the 1980s and then failing to get onto the same institution's media studies course, she is now heavily involved in PR training. She is an academic adviser to the London College of Printing and is helping to set up its first PR degree and masters-level courses.
Emma Gilpin, Time and Fortune Group international director of public affairs, an HMC client, believes Hobsbawm is best placed to teach the next generation of PROs: 'Julia's the networker's networker with the most envied little black-book in London.'
Now Macaulay has moved on, Hobsbawm is keen to build her own firm's reputation, but insists she doesn't mind if people refer to her as the former business partner of the wife of the Chancellor of the Exchequer: 'It's true - I am,' she says.
She is guarded about any mention of her former colleague, due to recent death of the Browns' baby.
Hobsbawm mentions her own two children, referring to them as 'my popsies'.
But she is all too aware of her former business partner's tragedy: 'I don't want to say anything that will upset her.'
Hobsbawm rejects the notion that she is a workaholic, but believes there is no such thing as a work/life balance: 'Just hard work in all aspects of life. I'm a networker and a matchmaker,' she beams.
Self publicist? Surely not.