The jurisprudence varies widely. I believe that the imposition of jail sentences has only recently become more frequent. Up until the last few years, the tendency was more to impose fines. However, often people did not pay their fines, because they did not necessarily have the money to pay them.
I think that over time, the courts saw that there was a problem. The phenomenon of contraband tobacco is growing. Now there is a tendency to impose prison sentences, but they are not very long.