Here, counter these facts:

Indoor cats...

have a life span of 12 - 20 years
are not exposed to disease
will not get abscesses from fighting neighborhood strays
will not be threatened by dogs or wildlife
will not suffer injury or amputation from leghold traps
will not suffer from frost bite
will not be hit by cars
will not get lost
will never go hungry
cannot be abused by strangers
are safe from chemicals and fertilizers
cannot be stolen
are happy living indoors

Outdoor cats...

have a life span of only 1 - 5 years
will be exposed to leukemia, kitty AIDS, parasites, etc.
will fight - causing expensive vet bills
are maimed or killed by dogs and predators can get caught in leghold traps
do suffer from frost bite
are hit by cars and injured or killed
do stray from home and get lost
can die from starvation
are abused by strangers
are exposed to toxic lawn antifreeze
are stolen
breed, if not neutered or spayed, and add to pet overpopulation

Disagree? Which of those things above are wrong? OK, I already know, where
you live you have none of those dangers right? I think Mary has the right
of it - fingers in your ears chanting lalalalalalalalala!

Hugs,

CatNipped