If you saw a good friend of yours abuse a dog they otherwise treat well what would you do?

My friends are wonderful people! Not a mean bone in their body but the are born and raised in Mexico where dogs aren't as well treated as here in America. The two dogs (yorkies) live great indoor lives, treats, always inside, shots, etc. Want for nothing. The only thing is when they pick them up the grab them by the skin anywhere they can, by their tail sometimes, one leg, etc. Also her husband will just be sitting there and outta nowhere for no reason "SMACK" will whale the dog with a punch or a slap for literally zero reason, almost a love tap cause he snuggles the dog once he does it... when i saw this i was saddened but must admit i bit my tongue not wanting to judge or offend, should i address this? He beats the dogs at various times through out the day and i really don't think he realizes it...