I have owned approximately 20 vehicles in my life, and of all of them, only 1 was purchased new.
1 was a 'freebie' because it didn't run at the time I got it, and another was a gift from my parents when I graduated high school (a 1984 Cavalier). The rest were purchased by me. Many were under 100,000 miles, but many more were higher mileage, including my current 2010 Fusion, which is now just about to hit 252,000 miles. I have had very good 'luck' with these cars.
The trick, as with any used purchase is due diligence - Inspect the car thoroughly, take it for an extended test drive, look up the carfax, etc.. until you have a good feel for the car's condition, history, etc.. If you do this, then the car is less of a 'gamble' and more of an 'informed risk', and IMHO, a low risk.
In my opinion, one can find some terrific deals by doing this. I got my 2010 Fusion in 2014 for less than $6000. There was a noticeable whine, but I did my research and found that the belt tensioner pulleys on these engines are prone to wearing out and making that noise. $45 on a new part and 90 minutes of work in my driveway, and it was fixed.