People (in the generalist sense) go mad for their smart phones and plasma TVs and so on, but don't always bear much thought to the factories that produce them and the workers who slave away inside. But those tech companies in competing in the marketplace take advantage of countries whose labour costs are low, and pared to the absolute bone for productivity vs. embedded cost. But that's mass production for you. What real choice is there? People don't want to pay more than they have to for Stuff, unless it's that good, and the marketplace has become designed that way. British-designed ≠ British-assembled ≠ British-made.
The British bicycle is a bit of a cottage industry now, perhaps a generously-proportioned cottage with a conservatory and an attic conversion, but even small outfits get frames made in Taiwan. You can buy a Dyson vacuum cleaner, but it'll be assembled elsewhere, unless it's one of the original series. Some things made in Britain were absolutely awful too, but stemmed from poor management and ill-judged business models, rather than outright lack of ability in the design or the production.
If I was a company director, I would be in business to make money, and part of that would no doubt be employing someone to figure out how to give as little of that money away to the Treasury. Being a good company director is about finding the best combination of ruthlessness and reasonableness.
I'd quite like to buy British, as much for supporting local economy as well as an overinflated sense of 'British', the time when we Made Things. The only bike I have that was designed and made in Britain is my Brompton. The others...well, no-one makes a bike like that here. And if we did, the price would have to be enormous to reflect cost of living.
K, interesting point about determining the break-even point for embodied carbon in food. Natural gas produces less CO2 than the equivalent energy from diesel trucks and gas-oil in ship engines, but the ships carrying in bulk might balance the advantage of a warmer climate. If the grid can be decarbonised significantly by 2050, as DECC predicts for an ideal scenario, home growing might make a real return.