Gentle not-quite-moderation note, I'd avoid using the word w*gs: in British English, which is one of the commoner varieties on this site, it's generally considered in the category of "probably don't say this even for exemplification purposes", because it's used very heavily as a racial slur in the UK, I wouldn't use it any more than I'd use the n- word. I know that unlike the n- word, those meanings differ quite a lot in other countries, but I'd suggest it might be ideal to use phrasings that don't include it.
I think you're right on the overall point though: the dynamic isn't imperial, or classist, given that wizards don't have to rely on the output of the muggle population. The concepts just don't apply well. Also, an integrated magical world would cause a lot of other quandaries. Sure, you could feed a lot of people by magicking up food... but you can also kill a lot more people, a lot more efficiently and a lot less obviously, with a wand than with just about any other form of weaponry short of tactical missile strikes. And the wizarding world clearly doesn't have infinite resources, because it too has classism and posh and poor families, so it's not clear that the proposed benefits of opening things up could actually be realised.