If your Barista is not allowing resuable travellers, simply place it on the bench and ask for the coffee & creamy milk to be poured directly into your traveller. You can then place your lid on yourself. No other hands touch your coffee and the environment is happier :)
We have witnessed many baristas only allowing the use of takeway cups and touching not only the cup but the lid as well when securing it. The only safe way to takeway your coffee is by using a resuable traveller.