I only ever wear proper cycling socks for cycling now. I used to get by without them in the past because I had a tight budget so didn't have much choice in the matter, but I had chillblains and cold legs in winter and sweaty althletes foot in summer. You get what you pay for. If you only make short trips by bike, don't sweat much, and don't ride competitively, you may get by in normal socks, but if you buy cycling socks you will feel the difference and won't ever want to go back to normal socks for cycling in. Same as with any piece of decent quality kit really. You can get by without expensive assos shorts, but the difference in fit, quality and technical performance is noticeable. If you can afford it, you don't have to get by with something that isn't designed for the purpose. You can choose to get something that is specifically designed for cycling and will make the whole experience more pleasureable.