Highly dependent on the region. In Germany and Austria [the only countries that I'm sure about :)], you're not as expected to tip as in the US for example, but it's still customary to do so.

If your service was bad, you don't tip. If it was okay, you may or may not tip a small amount. If it was great, yes, absolutely, you do tip.

> i.e. wages are very high in CH

That's probably because wages in CH are very high in general. Kind of evens out, seeing as the cost of living is equally high compared to most other countries in central Europe.