1) Who else is going to eat the pieces of food that fall on the floor?

2) Studies show that people with animals live longer.

3) There's a reason why you see "beware of dog" signs around houses, because potential robbers (not all, but some) stay away from barking and biting dogs. Guns are a great deterrent as well, but for some reason you rarely see "beware of gun" signs.

4) It could lead to a healthier lifestyle. Walking a dog twice a day compared to not walking at all will undoubtedly help you burn some calories.

5) It finally gives you a valid excuse to watch Animal Planet.

6) It gives you someone to share your hatred of cats with.

7) Because you love throwing Frisbees but hate playing with friends that refuse to "go get it."