In effect, is it really that different to a fine? It seems to have a couple of advantages, though: it's easier to collect, and it's proportional, so a person who can afford a fancy luxury car pays more than someone in an old banger, without the complexity of having to evaluate their income and savings.
Often these little practice amps are better than you think, but are held back by the stock speakers and cabinet. I got a Fender 15G free when I bought a guitar years ago. Recently, I populated the circuit board for reverb, added a spring tank, and swapped in a Celestion speaker, and it's now pretty good.
But a few weeks ago I ended up with another free Fender 15G! This time I think I'll build a new cabinet for it as well as adding in the reverb.