Defense against melee implements with a sword in modern day?

I was just in Wuppertal alter markt today at the street carnival and took my Svord knife out to cut a tag off a stuffed animal and the police didn't say anything even though they were standing right there. It's all about attitude and intent really. A middle aged man carrying a helium dolphin balloon walking through a fair with a woman and a small child in tow doesn't pose much of an objective threat of potential violence I guess. Now if I was 18 and with 5 of my drunk friends at the carnival and pulled a knife, then I'm certain the outcome would have been different and the cops would no doubt have been doing some paperwork on the matter.