Well, apparently the LC Smith people disagree with you, regardless that is the reason, they(the Smith shooters) didn't want people using repro parkers because there were no repro smiths. This may be a simple advantage of numbers/availability of quality shooting guns I don't know, but that is the factual reason.

Do any of the Repros have removable chokes??

Yes only the Sporting Clays model all of the rest were fixed chokes