Can being a vegetarian actually be a hindrance for some?
I have been vegetarian since 1/1/2000. It was originally a New Years Resolution, but it became a New Millenia Resolution. I figured that given impermanence it would not be too hard to keep. :D

That resolution arose out of an understanding that the mindless consumption of meat causes harm and death to many animals. Basically the resolution was simply to exercise restraint and not require the killing of sentient beings. 

Only much later did I encounter the suttas, so I started reading about and keeping precepts much later. And at that point the following made perfect sense, since I had already decided it was good principle:


  AN10.172:12.4: Not killing living creatures is a good principle.


I agree that being vegetarian can be a hindrance. Being "vegetarian" is a bit peculiar in that it has for some become a proclamation of virtue and merit that has somehow evolved into an obnoxious and contentious self-righteousness. And that would certainly be a hindrance.


  MN8:12.33: ‘Others will be stubborn, but here we will not be stubborn.’


I have found that gentle restraint suffices in body, mind and speech. A quiet explanation that "I avoid eating meat" is enough. And if asked why, I just reply, "it seems kinder."  

As my Zen Roshi used to say, "Road kill is acceptable".