But pinch to zoom is used for everything.
It's annoying as hell when you're holding a coffee and want to zoom.
In what way? If you mean one handed usage, it's pretty common here when people are standing on public transport, you need to hold on with one hand. If you mean the infrequency I need it, take a look through you're list of installed apps and tell me how many require zooming? Almost all are designed specifically to avoid it.