Succinctly and well said. You don't NEED golf shoes to play golf. Once you can afford some, buy some. Golf can be played and enjoyed on the cheap for strictly recreational purposes.
The person who started this is probably a novice but he has gotten a golf bug and he/she is frustrated or put off by its potential cost. Passionate, too. Let's cut him some slack, myself included after some reflection. Get a handicap; learn how to compete; and, along the way, as you improve and (want to) become a better player you will learn why the better players do certain things that are not immediately obvious. Entry level golf shoes are not expensive; check out ebay.com, too.
For my own, I started golf in tennis shoes, then borrowed my Dad's used golf shoes, then bought a cheap pair of Hush Puppies with cleats (showing my age), then bought a decent pair of golf shoes, then bought my first Foot Joys. Glorious. Along the way I also endured blisters, sore feet, slippage, a burst bursa-sac in my heel, and the inability on occasion to stay stable and fully balanced for a good, hard swing and better scoring -all owing at least in part to shoes that were not well-suited to the game. How does one know before one tees off what the course conditions are going to be that day or where your errant shots will land - dry, high or tight lies, wet, slopes, next to or in hazards, ... on and on. Many, many golfers are athletes, some gifted more than others; most of the good ones are "athletic" with good to great hand eye coordination and balance, no matter what their physical appearances. I think that on a given day I could shoot in the 70's in tennis shoes but why would I want to risk the enjoyment of the game over $50 to $200 invested for several seasons of play and many, many greens fees and hours of enjoyment.