How strict is immigration on taking dry spices back to U.S?

Greetings folks.  I have a bit of a dilemma.  A family member of my girlfriend has asked me to take a care package back to the U.S. for her boyfriend who also happens to be a good friend of mine.  She gave me two sealed containers of Maggi Sazon, which is fine, but she also gave me a one pound air sealed transparent bag of dry oregano, which at quick glance could be mistaken for weed.  I smelled the bag and it smells like oregano, but I told my girlfriend that I did not feel like getting stopped and having to explain the contents either upon arrival in the U.S. and most definetely not here in D.R. Since I have no rights here in this country.  I told her that if she had bought it in a traditional sealed plastic shaker container with a name brand attached, that would be fine, but that such a large amount of Oregano in a clear plastic bag, just seems like asking for unnecesary harassment in my opinion.

      I only hope she is not offended by me not wanting to take the package, I told her it had nothing personal to do with her, It simply opens up the possibility for delays either leaving the Island or upon arrival in the U.S.  Are my actions reasonable or should I just take the Oregano? Any insight is truly appreciated.  My girlfriend seems fine with my desicion, It is her family member I'm concerned about, thanks.