If you're not a bit selective with your technique, region, or breed, tomatoes aren't de facto easy. Any winter I'm not careful enough I lose mine. Other people struggle in dry summers, wet summers, or other adverse conditions.

Peanuts are IMO similar. They require warm nights and a long growing season, so any northern or moutainous area will need _some_ extra considerations and can't rely on cold-weather breeds to paper over the problem. You might want a much longer stint indoors than other plants before tossing them in your garden. Like tomatoes, they're not crazy about excess moisture (and where tomatoes just die when they get fungal infections, there's a wide range of conditions where peanuts will still produce but the produce will be toxic). Otherwise they're pretty easy.