there is IMO a difference between:
Writing a cv in such a way as to highlight the qualifications/skills you have that are relevant to the position you are applying for.
and
Deliberately lying on an application form when full information has explicitly been requested - thus not disclosing.
The former is perfectly acceptable, IMO, the latter is not.
I absolutely see why you would not put certain qualifications/employment details on a cv for jobs that do not require those qualifications. Apart from anything else, in the current market employers are often left having to sift through countless numbers of CV's, so the more irrelevant qualifications you have, the less time the sifter is likely to spend on your cv because they will have enough with relevant quals/experience.
But I think that if the questions are asked then you should disclose. It's not something that is likely to be found out, but it's still non-disclosure, and should an employer find out then you would be less likely to have a chance...
I have a slightly different albeit similar issue - I am currently applying for jobs, but I am visually impaired. Now, being VI shouldn't make a difference to my employability, but it does. People shouldn't be allowed to discriminate, but they do. The line I take is that if the question isn't asked, then I don't tell. They don't actually need to know after all, and if I get to interview stage then I explain about accessibility, etc. But if the form asks, then I do always disclose, because I think that not doing so will put me in a worse light. I think that's fine.