I'd be happy to be proven wrong, but I think that routers are a pretty geeky thing that most people don't want to hear about. I had offered to buy and set up a pfsense router for my parents for a few years ago and they were decidedly not interested, even after I tried explaining the merits of it. Pretty much anyone who is going to be interested in DD-WRT is going to be someone who can set it up themselves.

pfsense can sell for a relatively high price, I think, because they market themselves more towards businesses and big corporations.