Comedy in both countries had its origin on radio, with shows staged in front of live audiences. When TV came in in the 1950s, this same production technique was continued. But when Hollywood got into the act and sold more and more shows to networks that were produced in their traditional filmed-on-a-soundstage method, canned laughter was brought in to "sweeten" sitcoms. The mold was broken in the US in the 1980s with daring shows like Hooperman with no laugh track. But it was The Simpsons which really drew a line in the sand and insisted on going out without giggling taped idiots to tell the audience where the jokes were. Revolution! Now the landscape is filled with successful series like Malcolm In The Middle which don't rely on fake laughter interrupting the show.
But Britain clings to its traditions, and nothing is more traditional than the BBC where laugh tracks still reign. (Though ironically, when they imported M*A*S*H in the 1970s they insisted that Fox strip the laugh track off the show for British consumption. It must be a shock when Britons visiting the US watch a M*A*S*H rerun and hear gales of laughter permeating the show all of a sudden.) ITV, which isn't exactly synonymous with comedy, now is the pioneer in this matter with several series with no laughter including The Grimleys and At Home With The Braithwaites. But it's business as usual in the Light Entertainment division of the BBC with groundbreaking shows like The League of Gentlemen still belabored with a post-production laugh track. In one fit of insanity, 1981's Hitchhiker's Guide To The Galaxy nearly had a laugh track added to it, with an audience brought in to add giggles and chortles to the finished show, but thankfully saner heads prevailed and dropped it (you can see the results briefly on the Making Of The Hitchhiker's Guide To The Galaxy video). A few productions still manage to escape the laugher's curse at the BBC, particularly deadpan shows like Carolyn Aherne's Royle Family, or the self-parodies of Steve Coogan like I'm Alan Partridge.
Here is what I'm proposing: shows that are taped in front of a live audience should continue to use the actual laughter that is recorded at the time. But comedy shows that are filmed on location should be spared this indignity. Give the audience some credit. If we aren't laughing, it's probably because it's not funny to begin with!