Asterix, especially the later albums, is absolutely hilarious
, owing to the genius of René Goscinny
But he does it all with well-known techniques of comedy
For example, the line "orgies, orgies, we want more orgies" is repeated over and over by an actor, during rehearsal for a play designed to shock the audience. It's the contrast between the content of this line and the matter-of-fact way in which the director is trying to figure out his scene ("Perhaps you could throw something at him at this point? A tomato, or something.") that creates the fun. We have all the techniques: repetition, exaggeration, dead pan delivery (the scene is presented as if we're watching a documentary), silly detail (the tomato).
Asterix also excels in contemporary references to 'the real world'; this scene, for instance, refers to a new radical movement in acting that was important around 1970. However, missing most of these references - and I do - doesn't make it any less hilarious.
About translators: I can't agree more. I've even seen a joke unique to a language that I hardly know: questions in Latin end in -ne, so at one point we see "Hmmmmmmmm?" translated to "Hmmmmmmmne?"