Although I am very happy for the people who have had such tolerant employers and co-workers in the professional world, I have to agree with Axon. I am in the same general profession as quinnn and I was not so lucky. Before entering the teacher education program I was in, I needed more experience with urban (it was a program specifically geared towards this population) students so my advisor set me up with a teacher in an urban school to help out in the classroom. I wasn't expecting this and had just had gotten a vertical labret so I emailed this teacher, explained the situation and asked if it would be ok to wear this in the classroom and let her know that taking it out and letting it close was fine by me, but she said there was no need for that and it wouldn't be a problem. To my face she was pleasant and welcoming and I had noticed that several of the parents had facial piercings as well. I had a wonderful time in this classroom a learned a lot about the kids. The teacher agreed to write a letter of recommendation and said I worked very well with the students in a challenging classroom.
When my advisor met with me for the final interview for the program she said there was a problem. She told me that the teacher I had worked with (and had been so nice to me) was offended by my piercing and said the parents were bothered by it (no one said anything to me) and thought it gave me an unprofessional appearance. She also did not write me the letter of recommendation that she promised she would, which was a form to be sent directly to the school. I mean how passive/agressive was that?! So I had to basically plead my case with the advisor and show her the email where I had explained exactly what I had and asked if it would be a problem and the email where she said the piercing was fine. I also had to explain all the work I did with the kids in detail because apparently the teacher was not thorough enough in her report about what work I had actually done with the kids. My advisor let me in the program on the condition that I hide any and all mods while in the school. From then on I made SURE I hid any trace of a modification. There is a reason why I have never posted a picture showing my face on here or any other information that is specific enough to make me identifiable by a potential employer. Call me paranoid, but I would rather be safe than sorry.
When I was student teaching in a different district there was an intern in the school with several visible facial piercings and again everyone was sweet to her and some even asked questions, but when she wasn't around they commented on them and said they were "gross" and talked about how they hoped she wasn't expecting to get a job looking like that. I actually think piercings (including stretched lobes) are looked down upon more than small tattoos. I have seen a few teachers with little ankle or shoulder blade tattoos, but they even warned me to keep mine hidden until I had a teaching position and told me each school is different on their views on tattoos.
I have asked schools how many certified elementary classroom teacher applicants have applied to a position and the numbers are around 100 applicants per position that have been deemed qualified by the school board (meaning they are certified, filled out the app and have letters of reference and college transcripts and all that jazz) for urban schools and around 300 for suburban schools. Now when the competition is that stiff they are looking for just about any reason to eliminate you from consideration. Show up for an interview with 5/8" lobes? Forget it. They've got 11 other articulate, educated, experienced and qualified candidates with an interview and about 90-290 back-ups. Adwoa hit it on the head when she said "tolerance can also be affected by need".
Sorry for the looooong post, but I just wanted to share both my personal and "fly on the wall" experiences with mods in the professional world. Again I am really happy for everyone that has had a positive experience and I am not trying to say it is impossible, or even hard to find acceptance. However, like Axon said it is important to not give him what may be a false hope that he will be as lucky with his experience. I don't know if it's my locality, chosen profession or just bad luck but I am a case where piercings are not accepted and if he were in my shoes surgery would be a necessity as 5/8 lobes would not be an option no matter how well he can do his job.