Nick:However, is it fair that retail font manufacturers have to compete with custom fonts that are given away free (e.g. bundled) to help promote some other product such as computer operating systems (Microsoft), software applications (Adobe), and now books (Brill)?
Plenty of fonts suitable for English text are available free or bundled, and that doesn't seem to have killed the market for retail font licensing. The market is relatively small, but then it always has been: the people who actually spend money on fonts are professional designers, typographers and publishers. Personally, I think cross-licensing and the subsequent commodification of retail pricing had a much greater impact than bundling. Small foundries are not competing in the retail market against the availability of free and bundled non-retail fonts: they're competing against companies with large libraries flogging each others fonts for peanuts.
Is there a viable scholarly market for retail font licensing, i.e. is there a sufficient paying market to cover the costs of developing specialised fonts? I'm not sure that there is. Certainly, a company like Brill -- which is hardly a ‘large corportation’, Nick -- finds itself in need of commissioning custom types precisely because no off-the-shelf fonts support everything that they need to support. Having made the decision to invest a large sum of money in custom font development, you can hardly blame them for looking at ways in which to maximise the benefits of that investment. That said, I'm happy to raise your concerns when I go to Leiden in November and discuss plans for the fonts with Brill's director.
I had a pleasure to advise an academic client on the question of fonts recently and they ended up with Andron Mega. The person in charge of the project wanted old style figures, and their old font TNR didn't have them. The glyph coverage was a major issue.
Are Greek scholars (as opposed to publishers) a viable font market? Why shouldn’t they pay for their fonts?
As someone who works with classical scholars, I think I can say that the answer is "no". There might be an odd individual here or there who has enough publishing or design background to care about fonts, but for the most part if Gentium or Cardo is out there for free, they see no reason to pay for Arno Pro or the Modern Suite. They use Word, not InDesign, and they use whatever fonts came installed on their system, except when they need special glyphs (thus Cardo, for example). Classical scholars, and university departments of classics, and especially classics students, tend not to have very much money. They'll spend it on books first, and considering how much books from Brill cost, there won't be any money left over for fonts ;)