I agree, I do hope that shah_siddiquee isn't put off or offended by all the critical comment about these supplies.
I agree wholeheartedly with your post, fernando_g, and remember similar radio and TV sets we had over here that had a live chassis. We also had a pretty lethal mains power system here, with unfused plugs, plus it wasn't uncommon to have no earth connection to appliances. I can remember my mother standing on a chair to plug the electric iron in to the ceiling pendant light fitting, with a two core cotton insulated cable wired to an adapter!
Over the years we've massively improved electrical safety in the home here, and probably also in the USA and other Western countries, but it's clear that other countries are still back where we were in the 1950's when it comes to electrical safety in general, and with the advent of the internet and personal global trade it is easy to buy items that are intrinsically bloody dangerous.
As it happens, I ordered some small "12V" lithium battery packs from a reasonably reliable Chinese vendor, that has an EU-based warehouse (Banggood). I didn't want the mains chargers they came with, just the battery packs, as I know that these are well-made and have good cell protection built in. They arrived yesterday and the "UK specification charger" was a dodgy Chinese spec one, with a positively lethal, unfused and unshielded adapter. These adapters seem to be very common, so common that I probably have half a dozen that I really should throw out. Here's a photo I've just taken of the things:
Here in the UK these are technical unlawful, for a host of reasons, but the main ones being that they bypass the safety shutters we have on our outlets, that are operated by the longer earth pin on a BS1363 plug and which prevent anything being poked into a live outlet, and there is no fuse, so the plugged in device and its cable is not overload protected (the only protection would be the ring main fuse or circuit breaker, commonly rated at 32 A on our 230 V nominal system). Additionally, internally the contacts in these adapters are extremely poorly made and are often barely touching the plug pins, so there is a significant risk that they would overheat or spark internally.
We do have proper travel adapters that are safe to use, they have an internal fuse and spring-loaded shutters over the two pin connection, plus they are marked BS1363/3, to show compliance with the regs.