I think any mandatory charge should be included in presented prices... Maybe that is just coming from country where I don't really need to calculate any of added taxes and so on.

True I think ideally menu prices include everything. However if you're trying to transition away from tipping, calling out service separately reassures customers that they don't need to tip on top of what they see on their bill, and that the overall cost hasn't changed, assuming they would have paid the service charge voluntarily as a tip.

That's common in many places in the UK as well. And, in the US, it's pretty standard for a mandatory 18% to be added to the bill for groups. (The thinking is that a server could be really screwed if they worked all night for a group that under-tipped, as is easy to happen with a big group splitting a bill.)

I don’t think anyone has a problem with that, as it’s clearly stated on the menu that there is an 18% charge.

I wouldn’t have a problem if the menu stated all items will have a mandatory extra 18% charge for gratuity. I would gladly pay it. I simply want it to be clearly stated and transparent.