It’s really not desirable to use CD Track End Markers at all anymore - use CD Splice Markers instead. I don’t know of any CDs that have been adversely affected if you use CD pause times (with or without audio like the audio “hidden” in the pause you’re describing), but MP3 and standard iTunes albums are affected for major label releases, because their source files are ripped from DDP or CDR master without (not only the hidden audio you’re talking about), but the entire pause time itself. So if CD Track End Markers are used, the MP3 album or standard iTunes album will have different, shorter “spacing” between songs than the CD. That is unless things have changed recently, but i don’t think they have.
iTunes MFiT is not affected by this because the mastering studio supplies the source files for MFiT, normally with the “end-space” included.
I don’t believe this is an issue at all with services like CD Baby and Tunecore because of the way the source files are made (could be wrong though), but it is an issue with major label releases, so it’s safest not to use CD Track End Markers at all.
re: the Wavelab DDP Import Options, I find the word “Standard” confusing because it’s really not the standard import used by any company I know of. “Audio In Pause” is the standard import method, so that any possible Audio in Pause audio is not lost. I would hope at some point that “Standard” would be reworded or a warning of possible lost audio in pause attached (which could even be just desired tape hiss between tracks). I think all the options should be kept but “Standard” reworded.
EDIT: so yes, the DDP is not unalterable, and is subject to the setup used by the receiver. And they could edit the characteristics after open/import. They wouldn’t intentionally mute your audio in pause, but it’s a little more complicated than considering your DDP locked and “set in stone”, as seen by the import options available in Wavelab.