I can from my very own experience testimony this:
Yesterday a friend was targeted by some bandits, This was on the A7 south of Alicante near ELX/ELCHE. They drive across the front to block you in then the driver gets out with a map in his hand and asks for directions in English. It seems to be 2 men in a black car. The other couple were both in...
vwcaliforniaclub.com
Luckily it's the only bad experience I had, after decades of driving in (mostly Northern) Spain.
I have a local car with a Belgium numberplate. Sometimes I think about taking on a Spanish registration, to avoid this 'target' sign. The advantage on the other side is that I noticed over the years that in regular traffic control the police often let me pass when they notice my plate, avoiding the language fuzz it brings them. Or was I just always lucky?
(edit: just a side question: as my car stays there the whole year, I take the initiative to go to a local technical control each year, of which I get reports. Anybody aware of the 'legal' status of this towards insurance companies?)