That's only if there is a walkable path the to amusement park.

Most amusement parks are either located further out from the city, surrounded by a massive parking lot, or is enclosed by highways and non-walkable car infrastructure.

Take Six Flags Magic Mountain for example. If you look at the satellite view, you'll see that the closest residential home to it is a 46 minute walk despite being only 1000ft (300m) away from it. It's completely unshaded with literally nothing in between the house and the park. If you get a heatstroke, you're shit out of luck.