The majority of pubs or bars that I visit would quite often have a glass or jar on the bar where tips can be placed. I assume from there it would get divided between the staff. Generally, if I get a pint for $6.80, the 20c will go in the tip jar each time. If I'm eating, then it all comes down to the quality of food and service. Basically, I'll tip when I feel it's called for. And if I visit somewhere like the US, I'll continue that. If I see a bill where a tip has been added, they won't be getting it.
Tips are for exceptional service, not for doing your job or for topping up your income. That's your bosses responsibility. The assumption of a compulsory tip is absolutely laughable to me. Don't get me wrong here, I have a good enough income to be generous and usually tip 85% of the time. But when the place I'm at tries to tell me to tip, rather than letting me decide, then that's just going to ruin any good impression I have if the place.
On the topic though, when I do tip I expect it to go to the staff. Either directly to my server, or preferably into a pool to get divided at the end of the night. This makes it a lot fairer on the chefs, kitchen hands and door staff who may not get to deal with the customer as directly as the wait staff, but are none the less integral to the running of an establishment. I have a lot of friends in hospitality and almost every one of them receive their tips under that kind of system. If I knew that tips were going into the till and directly to the business, I wouldn't leave a thing. That's what their posted prices are for. If they want more money, raise their prices and ensure the quality justifys it.