I understand the "give them an inch and they'll take a mile" worries,... but I can't start to understand why anyone would be against the no fly no buy thing. Are you worried about being on the no fly list yourself? I'm not, so it sounds like a good preventative measure to me
If you have nothing to hide then you really should never plead the 5th and you should always consent to a search, right? After all, nothing bad can happen if you're innocent.