I can see where your in-law’s coming from, but to put a finer point on it:

Veganism is a philosophy and way of living which seeks to exclude—as far as is possible and practicable—all forms of exploitation of, and cruelty to, animals for food, clothing or any other purpose; and by extension, promotes the development and use of animal-free alternatives for the benefit of animals, humans and the environment. In dietary terms it denotes the practice of dispensing with all products derived wholly or partly from animals.

That’s why vegans aren’t interested in “cruelty free” animal products. It’s not just the fact that there is still a lot of cruelty involved; we’re opposed to animal exploitation regardless. Veganism naturally came out of the animal rights movement.