Let's start with the most obvious feature of the PlayPlace, those awesome crawl tunnels. Your parents might have been calling you to get in the car, but let's be real, there's no way your dad could actually fit in there to drag you out. Advantage: kid.
And if you had some bully big kid hogging up all the good spots, no sweat. There were a bunch of Nintendo 64's just outside waiting to be played. Just, uh, bring some disinfectant before touching those controllers.
If you lived in a forgiving enough climate, some McD's even had an outdoor PlayPlace (sometimes called a PlayLand). Sure, the carousel basically had the motor of a music box, but you were three years old and this was a ride. What, were you going to complain or something?
The hardest part for me was when we'd go to McDonald's, my parents would make me sit nicely before I was allowed to go into the PlayPlace. Thankfully, I was able to wait out those excruciating hours (probably more like 45 seconds) on these fancy, schmancy burger seats.
One thing that simply cannot be understated about the appeal of the PlayPlace was the total lack of supervision. To put it bluntly, there were no employees watching to make sure we played safely and didn't crowd the slides. It was like stepping into our own sovereign kingdom.
What exactly were FryKids again? Little pompoms made out of colorful French fries? OK, to be honest these guys never really spoke to me, but they were short enough that they made for fine chairs in a pinch.
If you were at a ritzy McDonald's (that is to say, where land was cheap enough that they could build on a big plot), sometimes the PlayPlaces came with an overflow seating area just for kids. Never had dipping French fries into our milkshakes without judgement from Mom felt so liberating.
If you got one of those tear-off cards in the mail announcing that a classmate is having a McDonald's birthday party, you knew you were in for a good time. Also, you probably didn't have to bring a very expensive gift.