Over 30 years ago I bought (or had parent buy) some Master System games at full price.
Golden Axe may have been the top at 275 Finnish marks, maybe around $65 at the time.
Most expensive I actually paid myself may have been Asterix, 150mk/$35.
Ever since I've only bought second hand, have never paid for a PC/PS1/PS2 game more than 80mk/$20.