Personally, my animals are all inside animals. They go outside to play, potty, and just roam and sniff but when they're ready to come back inside they're allowed. They prefer being around me and I don't mind them following me around
Our backyard is completely grass so they stay pretty clean going in and out, no mud in the paws, etc. If they do get dirty they either get wiped off and brushed or a bath if it's really bad
I really think it depends on the dog. As long as shelter, food, water, attention and training is given and the animal is happy I don't care whether they're inside or outside animals.
Jasmine - Female Miniature Poodle - born Aug 15, 2010
Loker Delgado Von Stalworth - Male GSD - born Jan 26, 2012
Koda & Zazu - 5 year old male cats
Alex - Male Cocker Spaniel (rescue) - RIP Cuddlebug 2007-2010