Living in Switzerland is much more expensive than living in Italy (housing especially), so salaries are more or less adjusted accordingly to the cost of living.
A relative adjustment might still mean a large absolute difference, though; I don't know about Italy and Switzerland, but even paying double for a house in Luxembourg compared to an equivalent in Portugal, and not earning double, I still had more money at the end of the month.
A relative adjustment might still mean a large absolute difference, though; I don't know about Italy and Switzerland, but even paying double for a house in Luxembourg compared to an equivalent in Portugal, and not earning double, I still had more money at the end of the month.