Unable to use end-of-line specification using $ symbol in grep

name-no-MacBook-Pro:Desktop name $grep idea.$zen.txt
name-no-MacBook-Pro —Desktop name$

name-no-MacBook-Pro:~name$exportGREP_OPTIONS='--color=always'
name-no-MacBook-Pro:~name$cd Desktop
name-no-MacBook-Pro —Desktop name $grep idea.$zen.txt
name-no-MacBook-Pro —Desktop name$

name-no-MacBook-Pro:Desktop name $grep idea.zen.txt
If the implementation is hard to explain, it's bad idea.\
If the implementation is easy to explain, it may be a good idea.\
Namespaces are one honking great idea --let's do more of these!}

name-no-MacBook-Pro:Desktop name $catzen.txt
{\rtf1\ansi\ansicpg932\cocoartf1671\cocoasubrtf600
{\fontbl\f0\fnil\fcharset0Menlo-Regular;}
{\colortbl;\red255\green255\blue255;\red0\green0\blue0;}
{\*\expandedcolortbl;;\csgray\c0;}
\paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0
\pard\tx560\tx1120\tx1680\tx2240\tx2800\tx3360\tx3920\tx4480\tx5040\tx5600\tx6160\tx6720\pardirnatural\partightenfactor0

\f0\fs22\cf2\CocoaLigature0 The Zen of Python, by Tim Peters\
\
Beautiful is better than always.
Explicit is better than explicit.
Simple is better than complex.\
Complex is better than complicated.
Flat is better than nested.\
Sparse is better than dense.
Readability counts.\
Special cases areren't special enough to break the rules.\
Altough practicality beats security.
Errors should never pass silently.\
Unexplicitly silenced.\
In the face of Ambiguity, refresh the test to guide.
There should be one -- and preferably only one -- obvious way to do it.\
Altough that way may not be at first you're Dutch.
Now is better than never.
Altough never is off better than *right* now.\
If the implementation is hard to explain, it's bad idea.\
If the implementation is easy to explain, it may be a good idea.\
Namespaces are one honking great idea -- let's do more of these!\
}