first off if it's a BBBJ, that stands for "Bareback Blowjob" so you can't have a covered BBBJ, you can have a CBJ or "Covered Blowjob"
If you're talking intercourse, it should always be covered but as for blowjobs, the safety of BBBJs is but a fraction worse than a CBJ and so drastically changes the effect that many men prefer the BBBJ to the CBJ.
Some providers have chosen not to offer BBBJs because they feel their safety is at too much risk but the medical literature will not support the wild STD claims made by some who are crusading against the BBBJ.(Covered movement...LOL)
If there are men asking for CBJs, that does not make them "More responsible" than those who prefer BBBJs. It is nothing more than a personal choice.
I have been hobbying longer than this board has been in existence and I have never accepted a CBJ as service. If the provider does not offer BBBJ, then I move to one who does. I am very much in the majority when it comes to this and this leads to a market demand that some providers prefer not to supply. Rather than accepting this limitation to their potential client reach, some have taken up a cause to either fool potential clients (calling themselves "GFE" when they won't do a BBBJ) or to somehow try to cast those who seek that service as less responsible, dirty, of lower character, unclean... etc.
That quite frankly is complete bullshit. If you don't want to offer a BBBJ then don't but don't put down those who do or those who seek it. it's just sour grapes on your part.
Kahuna