Go to the local big box everything store and have shopping cart races on the far end of the parking lot.
Don't scratch any cars.

Go to a nursery / garden center and pick out one small live plant. It is very romantic.

Go to the local river forks at dusk while the lights of the city come on. Snap a few photos, but be ready to jet out of there. Not very nice local usually.

Find somewhere with a ping pong table for free, bring your own rackets and balls.

Frisbee golf.

Food court !!

Local college or university has a geology collection / display.

Bring your cafe purchase to a local park.

Stroll by a duck pond... feed the ducks.

Bazaars.

Hikes in nature. Often hiking trails are available near you.

A park near us hosts a night when people with telescopes drive out of the city and set up, and people without telescopes can chat and ask for turns looking through the telescopes.

The dollar theater lives on !!

If you live in a different state than where you went to college, find out which sports bar in town hosts all the games of your alma mater, and mix in and cheer with like-minded alumni. Bring a couple extra bucks to buy a t-shirt, if they're selling them.

Go to your local town hall or visitor's bureau, find a chatty lady, and get the scoop on free plays in the park, free concerts, free fireworks displays and free children's events.

Battle re-enactments and airshows.