Getting your female spayed means less dealing with period blood, and dealing with male dogs being assholes around them. Even neutered males act up around a female in heat - we had an unspayed female at the dog daycare business once, was paying attention to other shit and sure enough, I ended up with a neutered male and the female stuck together for a few minutes.
The unspayed female was a husky with neurological issues (seizures and shit) that they didn't want to risk putting under anesthesia to do a spay.
Getting your male dog neutered means less dealing with horny dog behavior. Seen lots of that.
Overall it's probably not necessary but it's certainly convenient, and I don't have any ethical issues with spaying/neutering.