IIUC VBs are ideally used in very cold (e.g., below 20F) dry conditions where sweat is less of an issue. I don't think you necessarily used them incorrectly, but the typical reason for the whole bread-bag thing is to keep soaked shoes from soaking socks and leading to freezing feet. It's what mom did before sending us out to play in the (always slushy) snow when we were kids.

For trail travel I'd wear a thin inner sock, then the VBL then an outer sock. But as I never hike in the super-cold I've not done this myself. Generally, I prefer WPB gaiters. (Have use a VB sleeping bag liner.)

I've used neoprene socks and Goretex socks cycling, and they're a huge help. It's hard to keep feet warm on a bike.
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--Rick