I wouldn't bother, even in France and SPain I have had no problems without a sticker.
In Africa or other Muslim countries it might be an advantage.
I was travelling in southern Turkey a few years back and US/UK were bombing Iraq, we got screamed at in restaurants & bars a couple of times, that US/UK Govt were to balme etc - once went down the road of being Welsh, and showed tham the flag on a diary - the were clueless as to where that was. Second time we said we were froom NZ they went away and came back twith a drink as an appology. Elsewhere throughout Turkey, Syria, Jordan etc we had no problems.
We were camping out in Jordan and were approached by an Iraqi/Jordanian group - large extended family of 50-60 - they invited us to join them, they were fully aware we were Brits, one of the elder ladies then explained that two of here sons and three son in laws had died in Gulf Wars etc - thaey were very realistic and balmed it on political manoevering.