I tend to pay on cards in restaurants, but will tip 5-10% depending on service and what change I have on me (and usually take some change for this purpose). I understand the 'they get paid for doing a job' / 'no-one pays me for doing my job' arguments but still feel a moral obligation to do so. Probably is double standards as I don't tip anyone else except taxi drivers and hairdressers. Tipping taxi drivers is becoming more grudgingly as more tend to have radios blaring, have to be told how to get to my house (learn the fooking street index!), or charge stupid amounts for short distance (admittedly company's charges).
I'm also beginning to regret tipping my hairdresser. Mine only costs about £10-£12, but it is effectively short back & sides and 15-20 minutes work. At that rate she's on over £30 an hour (they are always busy so no real quiet periods). She spends half her time chatting to her colleagues, and I don't think ever really cuts it the same way twice. On the plus side she is fit.
What really annoys me is when with a group someone won't offer a tip (as with Mr Pink). I understand they may not normally tip, but when with a group it can cause a bit of friction. My Father-in-law never tips, so I then feel awkward and end up putting more in myself to compensate. I wouldn't mind too much, but he's loaded. He was also quite happy to accept tips himself when he had second job as a taxi driver.