There has been a bypassable donate button for years. I expect the current stance is because almost no one donated, just downloaded with no support. I do not know for sure, but I would guess the web site administrator has logs (although given the reputed state of the web site, perhaps not 
) that tells them how many downloads against how many donations. They will certainly have logs of how many donations, and I expect github’s analytics will tell them how many active copies of Fritzing there are, by Fritzing-parts repository downloads (which with Win7 dead for updates will be under reporting.) I would also point out (as a former network operator, I know bandwidth is not free) that someone, I assume partly donations, has to pay the hosting and bandwidth charges for the web site and forums (and I have been hopefully running them up lately with the parts creation howtos .) It is a hard choice, but I would rather see Frtizing survive, and from what I see, that is still in doubt, there appears to be a lot more wrong than was realized when the original time line in the github post was made (no distribution chain, broken web site, probably more I do not know about.) That said there has been great progress too, the distribution tool chain has been recreated (possibly better) and the release is getting closer, for a while you could get the windows and Mac binaries on github but something broke there and you no longer can, but progress is being made. The github issues page has been triaged (I was encouraged to enter my long list of problems that I have kept locally a week or two ago, when Kjell committed 5 fixed bugs in gerber processing to the development branch.) But without funding that is likely to stop and then death by decay will occur for most people. which would be a pity. As was pointed out in one post or another (and I know from discussions in the forums about what happened before I came to Fritzing), it got as far as it did because it was a publicly funded research project for a number of years (until the funding ran out.) That means the code and underlying design are both of high quality (I have seen that from reading the source, where the few comments are todo type items for things to come, the design has been thought through), the flip side of that is that it is going to be difficult to make it in to an open source project, the code base is too complex (I can attest to that too ), without anyone left that is familiar with it to help out (I have not found any one in 2+ years of trying.) Thus the funding to pay pros to do it. Again my $0.02 (or whatever low number the Canadian dollar makes that today, plus we no longer have pennies.)
Peter