On one hand, yeah, that sucks.

On the other hand, you go to a foreign country, you're subject to their laws, and it's on you to be aware of them.

There are weapons that I could happily lug around in the US that the UK would take issue with if I were to be doing so in the UK. Do I personally feel that British law is going the right way on this? No. However, it's British territory, and so British law has jurisdiction. Saying "but I'm from the US and that would be perfectly legal back home" isn't going to carry a lot of water with British courts, or, I expect, with British public opinion.

Similarly, a Brit can't exactly go to the UAE and just do as one does in the UK and expect the UAE to accept it because something's legal in the UK. International travel is a lot cheaper and easier than it ever has been historically, but once you walk across the line of a sovereign territory, it's got real consequences, and if you choose to travel internationally, it's on you to be aware of them. That country isn't just a tourism spot for people from Country X, but a home for people who live there. They've got their own rules and concerns.

The chief executive of campaign group Detained in Dubai said Mr Fakana felt abandoned by the British government. He's expected to appeal against his sentence.

I don't really see a reasonable complaint against the British government here, at least from the article text.