Indeed, for men, shoes are the hardest part to work around on a budget. Cheap looks cheap (and tends to fall apart really fast) and used is rarely actually cheap unless they're so beat up that, at best, you can manage smart-casual out of them. You can save money buying used, but "cheap" is practically unattainable.
The materials (leather, mostly) are just too expensive for actually-cheap men's shoes to be A Thing, at least for mainstream looks which basically all require leather shoes above a very-casual register. Even alternative fashions usually find a way for it to be hard to get away with cheap shoes, it seems (much "street" fashion, for example) usually subbing in expensive casual styles (pricey sneaker, or conspicuous-consumption work or military boot styles) for the oxford or loafer or whatever.
A guy once pointed around the room and described what 20 people were wearing, where they bought it, what it costs, how fashionable he considered it. I ask him what I was wearing. He said: I have no idea! Its so wrong that it works, its more refined than everything in the room. I cant imagine spending more than 10 euro on the set (shoes aside)