I think the root of all that goes way back. I've lived in Bulgaria for most of my life(with the exception of around 4-5 years during university). Back in the day when I was a kid and teenager(think 90's and early 2000's) gypsies were a big problem. I remember one summer when everyone went away for a holiday and there was just me and my mum in a 300 meter radius for around two weeks. A house was getting robbed every night during those two weeks. And we are talking pretty much the center of the capital.
That said, at some point(not sure when or how) that all changed. Now in the day-to-day life, gypsies cause no harm whatsoever. They are a minority and as such I have very little interaction with them but in the few instances I've had, they've always been very warm and kind and the once I've worked with have been incredibly hard working and devoted.
But even though I see a huge improvement, we need to look back a bit to see the root cause: I had the chance to meet some of my grand-grand parents and they all had roma friends when they were young in the early 20-th century. However there have been huge political campaigns against them(both socially and economically) between 1944 and 1989(even though those were flowered up as "integration" programs). I think what we see now is one of the many scars the regime left behind.