Not sure what kind of cutoffs you are looking at as reasonable. I went to a program with nearly a 100% rate (you didn't ask me), and it was only the occasional one person who did not match.
I think match rates need to be supplemented with class size information as well. What is your class size? If you have 30 in a class, and have a 50% match rate - that means 15 people EVERY YEAR do not get an APA accredited internship. That is a lot different than the occasional 1 person at a reputable PhD program.
Not to mention, that school then collects at least $120K in tuition from each of these 15 people despite them not getting the APA internship (see their website for the cost estimate
http://www.argosy.edu/programs/clinical-psychology-degrees-1211.aspx). That is probably generous since they list annual tuition as over 40K now on their stats page (
http://www.argosy.edu/documents/psydinfo/OrangeCounty-psyd-outcomes.pdf).
If we use the "good" numbers from 2011-2012, 14/26 students applying at your program got an APA internship internship last year. By my calculations, the Argosy Orange County campus still collected at least $1,440,000 from the other 12 students over the course of the program, despite them not matching to an APA-accredited internship (which is a minimal standard for many jobs).
At least the 1 person who didn't match at the PhD program was fully funded. And perhaps more importantly, the program could dedicate a lot of attention and resources towards helping that one student with next steps. I'd imagine with it being the norm at other programs, the culture would be a lot different (and I am assuming those non-matched students still pay tuition).