In point to point communications you are correct. But (gains not withstanding, and that is not the issue here) I have seen many many many situations where the bowtie outperforms a yaggi simply because it obviously has a much wider capture area and doesn't wind up with a null on one station while the rest are fine. And you know the only way to fix that..
There are plenty of cheap yaggis out there as well, but when you are trying to pick up several, possibly dozens of transmitters from the same site, the bowtie is a better antenna.
BTW- When the transition happened a few years ago, we bought bowties, yaggi's, 'panel' antennas, pulled an RV omni out of the junk pile, and went to the roof with an analyzer. When moving the antennas around simulating various mounting points, the bowtie won. Wasn't the strongest, but was the most consistent.