Hmm . .
Let's try an analogy. If you knew that car dealer A was importing cars, direct from the manufacturer, which had left hand drive and a speedometer calibrated in mph, would you believe Dealer B (whose prices were higher) when he told you that A's cars weren't 'UK spec'? I suspect not; there are certain characteristics which are specific to UK requirements.
The same is true of TVs. To be used in the UK, they must conform to the following:
Voltage = 230V (That's common to most of Europe, but not to the rest of the world).
Electrical frequency = 50Hz (Once again common to most of Europe but many other parts of the world use 60Hz).
Fitted plug: UK '3 pin square' type. (Not used in many other countries)
Colour system = PAL (Quite widely used but many other countries use SECAM or NTSC).
Version of PAL = PAL-I. (Apart from the UK and Ireland, this is only used in Angola, some parts of Botswana, the Falkland Islands, Hong Kong, Macau, Namibia & South Africa).
Putting all of those together, a 'UK spec' TV set will only work in the UK, Ireland, the Falkland Islands, Hong Kong & Macau. A TV set designed for any other market won't work in the UK. So, unless a few sets have 'strayed' from Hong Kong (which wouldn't affect their usefulness in the UK), you can be certain that any TV offered for sale in this country was designed to be used here.
Chris