Two fun facts: 1) unlike most styles, the cream ale is original to North American, born in the US in the mid 1800s; 2) the cream is, of course, an ale, but it is inspired by German lagers and "drinks" like a lager — it's light, crisp, and goes down easy. Okay, so that's what I do know; here's what I don't: what is a cream ale? And is there actually cream in it?
Spoiler alert: no, there isn't. Cream ales are simply light American ales that have an additional fermentable sugar sources like corn or rice to lighten the body. This makes the beer ferment faster, and therefore more economically; their overall lightness makes them easier to market to a wider consumer base than traditional heavier-bodied English style ales. At least that was the goal in the 1800s.
So, why cream ale? The cream here is likely akin to "cream soda," which also features no dairy. Cream, at the time, was used to signify something rich and decadent, with a silky texture.
To learn about the full history, check out this piece at BonAppetit.com: What Is Cream Ale (and Is There Cream in It)?