Virtual tipping is a horrible practice that may do more harm than good. But what are our other options?
Tipping waitstaff multiplies existing inequities. The young are tipped better than the old, the white better than the black. People born in America are tipped more than immigrant workers for the same level of service. And the biggest study on the subject shows that tipping does not correlate with quality of service at all. html 
It also breeds racism against customers, with American waitstaff famously not wanting to serve "black" tables because "blacks don't tip". html
In academia and online we rely on tipping in the form of citation, upvotes, and likes to similar discouraging effect. It might be time to consider the damage our tipping system may be doing.
As Kate Bowles mentions, however, it's not enough to just decide not to tip. Our service economy, our academic prestige, our online life rely on these mechanisms. Tipping is the assumption on which other things are based.
But how do we get out of this mess? Is there even a way?
Look a few paragraphs above, for example. I credit Kate with mentioning this idea. She's surely not the first person I've talked with about this. I've been talking about this issue with people for a long time. Dozens of people have influenced my thinking. Kate gets mentioned because she's closest to this moment in time and someone I've talked with and worked with over time. And I feel she's smart and "deserves" some credit. Her access to me and our relationship morphs into a citation that someone will not get from me.
Maybe because of that more people read her. She cites people she knows. She upvotes people she agrees with. Over time she gets credit for things that could equally be attributed to hundreds of other people, and manages to get credit for her friends as well. Privilege propagates.
People say this is an online thing, but I really don't think it is. I've been in meetings where I've said something ignored only to have someone else repeat it and come out brilliant, and I've been in meetings where I get credit for ideas despite my best attempts to give the credit to the lower status people who developed it.
Face-to-face group discussions are brutal and horrible when it comes to attributing who came up with what, and they almost never get it right. I mean this literally -- they get it wrong a greater percentage of the time than they get it right.
We expect more from the web, because it feels like publication. But it is thick and frequent publication, not a set of 10 disciplinary journals that come out 6 times a year. In the density of tweets and wiki and blog posts attribution will usually be wrong, just as it is in conversation.
A possible solution would be to do what coders did long ago -- end tipping altogether, see all ideas as revisable for others, discourage the idea that people can own a concept or a thought. I don't cite the sources of the very valuable coding tricks I've learned from others. I use them. If I do something novel, and I need people to realize the novelty (for a job interview for instance) I just follow the priniciple of Tell People What You Did.
And of course this is what a number of establishments have done with tipping -- they've raised wages, banned tipping (even as a voluntary practice) and by and large things get better (but only if you *ban* it, which is interesting).
That sounds nice, of course, but the fact is the world of programming is organized differently that the world of the publishing writer. Credit matters in academia and writing, and it's no good asking for unilateral disarmament. So what do we do?