Wow, income tax seems to be pretty low in Bulgaria compared to other European countries?
For 50k net per year, or ~4k per month, in most other countries you need to earn ~80k EUR per year (gross). In Bulgaria, you need ~57k EUR.
For 75k net per year, or ~6k per month, in most other countries you need to earn ~130k EUR per year (gross). In Bulgaria, you need ~85k EUR.
Go figure, these are really large differences and that very well might be the reason why we see a lot of big companies there. Tax is unusually low.