I always tip in cash, except in the rare cases where I happened to not have cash on me. I am always under the assumption that this kind of thing is the default

I always tip in cash, except in the rare cases where I happened to not have cash on me. I am always under the assumption that this kind of thing is the default not the exception; when you add tip to a credit card who knows what happens when the mothership sucks up that cash and filters it through various middlemen before finally (if ever) getting to the person who provided a service to you.