HE'S known around town as Mr Duty Free, a title earned after nearly 12 years as the mouthpiece of the well-worn slogan ''Hong Kong - a shopper's paradise''. But things are about to change: Roger Thomas - or Mr Here-there-and-everywhere as he is also known - is shedding his many titles. Gone is the title of public affairs manager of Duty Free Shoppers Hong Kong, he resigned as chairman of the Retail Management Association after his two-year stint finished, he has stepped down as president of the children's charity, Hans Andersen Club, and has even been selling off his possessions. There's a 50-50 chance, said Thomas, that he may be saying farewell to the territory. Thomas admits his decision to quit as the man most likely to be quoted on anything to do with the retail trade was a gamble, but said he simply felt it was time for a change. HE believes it's time for some of the new guys to move up the ladder and, as 1997 approaches, for local Chinese to take up the reins. ''To be totally honest, I don't know what I'm going to do next,'' said the 52-year-old on Friday, his last day with Duty Free Shoppers. ''I'm looking at the Middle East, at going back to Europe, I'm not averse to staying in Hong Kong or moving to elsewhere in Asia. I'm giving myself a few months off to think about it.'' ''But hey, with a beard like this, I'm first in line for Father Christmas,'' he said with a suitably jolly laugh. Yes, there has been one firm offer. A rumoured return to full-time broadcasting - with RTHK - was knocked back because the money was just okay. He could always take up consultancy and get paid for the advice he has been handing out free all these years. At any rate, speaking invitations are still coming in from around the world. ''If I went back to Britain, I would get involved in politics in someway without a shadow of a doubt,'' said Roger, a Conservative Party member. A family crisis in 1977 brought Roger Thomas to Hong Kong. His wife Jenny lost a child and the best thing to do, advised a doctor, was to get her as far away as possible. An RTHK ad for a broadcaster in The Sunday Times was the solution. ''The saying that you either love Hong Kong or hate it is very true. If you hate it you should get out. I took to it like a duck to water.'' But after four-and-a-half years, Thomas had had enough of RTHK - a terribly archaic institution then, he said, full of old-style civil servants. ''And I wasn't going to wait around to fill dead men's shoes.'' He was packing up to return to London and a job with the BBC World Service when he was head-hunted for Duty Free Shoppers. It marked the beginning of a public profile that has seen the opinionated Welshman pitting himself against any comer: against politicians, such as Chris Patten (''a pale imitation of the man who first came to Hong Kong''), against unscrupulous retailers,(''crooks, unethical scum'') and the ''rudeness syndrome'', which, as a former school teacher, he blames on education. And he realises there are those who will be glad if his soap box is pulled out from underneath him. ''Honestly, there are some people who would shoot me on sight, but I think they are in the minority,'' he said. But for now, Mr Duty Free is still talking. It is Hong Kong's future as a shopper's paradise which he fears has a big question mark hanging over it. Courtesy, or rather its disappearance, is something Thomas sees as a contributor to Hong Kong losing its shopping crown. ''Singapore, and I hate to say it, is streets ahead of Hong Kong. I don't know what has gone wrong. Maybe it's the push and shove of Hong Kong. ''Hong Kong thinks, breathes and eats money, the town has turned from a motivator into a humiliator. It's going to do Hong Kong more harm than good,'' he said. Quality, said Thomas, is another area which will see Hong Kong slide down the top-10 list of places to visit. ''Tailoring is a good example - the quality was much better 10 years ago and that's dangerous. Sloppiness is also a very dangerous thing now in Hong Kong.'' Pollution is also playing a part in turning away tourists. ''When I first came here there used to be a swimming event across the harbour. You'd have to be mad to even think about that now. ''The Dragon Boat races are potentially a big visitors' draw, now I actually worry about those guys.'' But now he's trading the rhetoric for the unknown. ''Now I've taken the decision, I feel quite euphoric, like a weight has been lifted off my shoulders. ''Sometimes in the wee small hours I've wondered, what are you doing? But when it comes down to it, you've got to believe in yourself.''