Several things here ........
1) When I first developed my breasts, it was as a result of hospital drugs. A later visit to that hospital found me talking to a lady doctor about how surprised I was to find how the breasts swung about and moved from side to side when I was doing jobs. (I am a 42D and 50 years of age). This doctor was one of these people to whom you could say anything, and she immediately understood all the implications and was very sympathetic. That was her great gift. She gently suggested to me and my wife that I used a bra. Straightaway I replied that surely bras were for women, but she countered that by saying "no, bras are for people with breasts" -and this from a health care professional.
2) Concerning a wife's possible reaction; Just turn the whole thing on its head. Could you imagine how the balloon would go up if you started giving your wife orders about what she could and couldn't wear? So, what right has she got to dictate to you what you can or cannot put on your body. In fact, it's surprising just how quickly wives get used to the whole business of a man using a garment that's a bit different.
4) It's been my experience that women are so endlessly interested in feminine accoutrements that when they find a man with whom they can have an intelligent and worthwhile discussion about clothes or make-up or similar feminine topics, they will value that man very much and seek out his company. Using a bra gives a man great insight into the many aspects of the whole business and it's been my experience that having that knowledge and understanding of how it all is for a woman makes you more desirable and valued in their eyes.
5) In these days of supposed equality, I think it's very unfair that women in our culture can enjoy going through life looking and dressing just how they want, and nobody is ever supposed to make comment about it. How would they like it if they had to have exactly the same unchanging hair style from the age of 2 months until the very end of their lives, and always be dressed in the same dark drab clothes every single day as we do. So much for equality, eh? So given our daily experience I would say they don't have much right to dictate to us about making use of a small barely visible undergarment.
5) Just using pure logic; If there's any hard or strenuous work to be done, it usually falls to the man of the house to do it. If both members of a household have breasts but only one of them ever does the more labour intensive jobs, then surely that one person is the one who is more in need of support. In other words, it could be argued that a man has more need of a bra because he is the one who does all the manual tasks.
6) Regarding how people see and notice things, when I was a teenager, as teenagers often do, I experimented with having a moustache and a small beard. It didn't amount to much and I soon tired of it. However, I decided to have a bit of fun. I shaved off one half of the beard and the opposite half of the moustache and left it like that to see if my parents noticed or made any comment. To my astonishment they never noticed a thing! Neither of 'em! As this shows, the vast majority of people go round with their eyes shut so don't be feeling that lots of people will be staring at you. They won't! As well as that, consider how you react when you see something unusual. You don't make a big song and dance about it. You might glance and then you're neither bothered nor concerned, -especially if you don't know the person.
7) There's a programme on television called "Naked Attraction" and one of the features that comes out of this programme is just how many people, of all ages, are walking around with all sorts of piercings or surgical changes made to their bodies. There are any number of good folks who are transitioning from one gender to another. Guys who are thrilled at every little growth in their breasts as they make their journey to womanhood whilst girls who eagerly discuss gender re-assignment surgery and methods of mechanically achieving erections in their new penile anatomies. One couple they showed was a fella dressed in a skirt and blouse who was hoping to become a woman, and he was actually dating a girl with a man's hairstyle and dressed completely in a man's trousers and shirt, looking very masculine and transitioning to becoming a man. What I am saying is that compared to the enormous number of sexual variations and different varieties of people walking around out there and who are all experimenting with just about every variation you could think of, then in the great scheme of things, just wearing a bra to help with a natural enhancement is really just small potatoes.
Piglet.