Not all WG's are ungrateful to be given gifts. Maybe some, who project a certain kind of image, maybe get a lot of expensive gifts and it therefore has become meaningless to them, but not all are like that.
Gifts shouldn't be required for good service and in my case, aren't required but that doesn't mean that a thoughtful gesture doesn't put a smile on my face. Sometimes you can make someone happy for very little - for example I had a repeat client who visited me later on on a hot day and brought me a cold 500ml bottle of Pepsi max because they thought I might appreciate a cold drink. 2 for £1.50 at the corner shop, but it was very thoughtful and I did appreciate it.
Never been tipped, not sure I would know how to handle that, I know it makes no sense but that would feel a bit cold after the fact?