Despite the allegations here being ridiculous (how is this use humiliating?), i do not find necessarily absurd to ask for a small fee for commercial use.
Iconic works of art like this one belong to our collective heritage (not just the italian government). But while the use of their image should be left as free as possible, unlike a poem or a novel, they are also real objects that require constant, highly specialized manteinance and care that has non negligible costs.
Is not that crazy to ask companies who profit from them to contribute back a little, so that those money can help the institutions that take care of these and other works of art.
Stuff in the public domain sometimes also require the public to take care of them.