To respond to several points in this discussion all at once:
I have a student who is active in his religion, and who has a problem with the title of "Master" for religious reasons, which I understand... but this same student refuses to call me (or my instructor, for that matter) by first name in non-MA social settings, out of respect. There are many ways of earning, and demonstrating, respect.
I also agree with the point that "Master" in an MA is, in some ways, equivalent to academically-earned titles - but I would tend to equate it more to "doctor" (as in Ph.D, not M.D.) than I would to "professor". My father is a college professor who holds 5 advanced degrees, including two master's degrees and a Ph.D., and prefers "mister" to "doctor" in deference to training and skill that medical doctors must complete and demonstrate - an opinion he has held since I was a child; I remember when I was about 8 or 9 (so 30 years ago) my father explaining why he expected my friends to call him "mister" rather than "doctor" (he earned his Ph.D. when I was 5), and that while he would allow his students to call him "doctor", he preferred "mister" or "professor" - for many of the same reasons listed about calling people "master". In my opinion, this causes him to deserve the title "doctor"
more than those who insist on it because they have that piece of paper.
In addition, I am Jewish, and, while Jews consider G-d to be "Master of the Universe", the connotations are somewhat different than the Christian perspective involving Jesus Christ; also, "master" is a term used in Judaism to describe a person who has devoted his life to the study of Talmud (commentary on the Torah, the first five books of the Old Testament) - and in Judaism, if you can, study Torah; if you can't, the next best thing is to study something else - in great detail.
In response to a discussion on this topic I participated in elsewhere, I looked up the definition of master, as follows (color added to emphasize parts of the definition that are, in my opinion, particularly relevant to this discussion):
from
http://m-w.com/dictionary/master
Main Entry:
1mas·ter 
Pronunciation: 'mas-t&r
Function:
noun
Etymology: Middle English, from Old English
magister & Old French
maistre, both from Latin
magister; akin to Latin
magnus large -- more at
[SIZE=-1]MUCH[/SIZE]
1 a (1) : a male teacher (2)
: a person holding an academic degree higher than a bachelor's but lower than a doctor's b often capitalized : a revered religious leader c : a worker or artisan qualified to teach apprentices d (1) :: a great figure of the past (as in science or art) whose work serves as a model or ideal an artist, performer, or player of consummate skill (2) : a great figure of the past (as in science or art) whose work serves as a model or ideal
For myself, I differentiate between a, b, and c; when I refer to a martial artist as "master", I am interpreting it as 2c1 and 2c2, with emphasis on mastery and serving as a model or ideal. While the latter portion could also be religious, I am not intrepreting/applying the term "master" in that fashion, although I can see where others might do so.
By this same token, I have no problem using the term "master" for senior BB's who have devoted their lives to a martial art - remembering that in ITF TKD one must be a VII Dan to earn the title "master", which equates to over 30 years of experience. My instructor's instructor began TKD the same year I was born (1966), and I have absolutely
NO problem demonstrating respect to him through the use of the title "master" - although I will also admit that my background gives me a different perspective than other people might have.
