I understand fans thinking that this episode is one of the worst in Buffy history, however I love it for a different reason.
Think of young woman out there being treated like they are special to someone, and then that someone uses them to get exactly what they want (sex) and then being thrown to the side so they can move on to the next one. Unfortunately this happens way to often in our society. We lack intimacy all the time. Every new show out there is so full of sex and violence that women and men have no idea what's real and what isn't. They rely on porn to full their void and the expect their relationship or lack there of to have the same type of meaning.
This episode shows us that Parker wants his ego stoked because my guess is in High School woman ignored him so in College he's using them. Buffy on the other hand only knows Angel and that when he truly loves her he turns evil. Buffy can't understand why Parker used her and Parker can't understand why she became attached. Add the comping mechanisms that we as humans do; drinking, sex, drugs and we get beer bad. Not to mention Buffy hitting Parker over the head with a stick. That part ruled! Yet she still saved his life.
Look at this episode as a marker for woman who give their heart to someone and men who believe their owed something from previous women. It's a shoulder shrug for sure. I like it!