McD's failing in customer service

Was at McD South Africa in Kenilworth Western Cape, drive through.

Requested breakfast with a coffee and one sugar.

On getting to the window for pick up, I politely requested for sugar to be added to my coffee, the lady that served me the coffee said; "No, I need to do it myself because customers are rude". (Exact words)

On attempting to find out why she would feel that way, she stated this is what her manager told her to say.

On taking my coffee she then asked me to pull away from the window as my food was not ready as of yet, I at this point opened the coffee at the window myself and added the sugar.

Explaining to the lady that although client was rude previously, myself as a polite customer was needing to accommodate McD's for not having my food ready by pulling to a parking zone, it would have been nice if she performed the same accommodation asked of me and simply added the sugar on my behalf. (I asked this because I hurt my hand and simply needed the assistance)

I worry that such a simple request has destroyed the opportunity for polite service from what was already a very frustrated McD's employee.

How far the mighty have fallen.