Are these acts (imitating the kuffaar) not bringing displeasure? What type of muhabbat (love) do you profess?
Look at it this way: You have a friend who professes to have muhabbat for you. You also have an enemy. Now, your friend, who professes to have affection for you, deliberately wears the clothes that your enemy wears. Will you be pleased? Will you tolerate it?
No, you will not be pleased, and you will not tolerate your friends action. So, how do you expect Allah Taala to be pleased?
That person, that Muslim, who believes in Me, has adopted the dress of others! Will there not be cause for Him to show displeasure? Definitely He will be displeased.
This persons religion has not changed. However, in his heart which should have expressed Islamic values at the practical level, that amount of change has occurred! Therefore, displeasure!
Coming back to your friend: He says, Brother, I have muhabbat for you.
Your response is, "That I do not deny. But, is this the quality of your muhabbat that you have donned the clothes of my enemy? Just how much displeasure are you not causing me? Just stop to think for a while!
In the same way Allah Taala is saying, 0 Muslim! I have specified for you an Islamic uniform, that, when you leave your home, you be recognised as a Muslim! From top to bottom, you should be identified as a Muslim!
The dread and fear that should have been in you, for Me, you have replaced with fear of My enemies? So much so, that you have changed your dressing and appearance? Is this how much you fear them? Whereas My khauf (fear) should have been greater than everything else!