Prunts have been used by many glasmakers and I do not think they are specific for any region. Venetian glass uses lots of prunts, mostly small ones. Bohemian and German forest glass uses somewhat larger ones. But in all older products these have a function. Prunts were used to stop greasy glasses from slipping through your fingers when passing them on during banquets - because the one guest one glass custom is relatively new. Companies like Josephinenhütte Teresienthal, Fritz Heckert and Köln Ehrenfeld all made traditional tableware with prunts "in the German tradition".
The really smack-on blobs in contrasting colours as a designer statement seem to be something from the 1970ies. I have seen those on Russian and Polish glass, Bang used them in the 30ies and so did Copier, they have been used in Italy and in Norway and Czechoslovakia. But Sweden and Belgium should not be ruled out either. In short, we're not getting anywhere with the item @ hand.