Yes they do indeed look more feline than Dogs as most westerners consider dogs. However, back in the day, there were dogs like the pug, and such. Which had larger cousins. They were nicknamed Fuu-Dogs. The dogs you more commonly see guarding shrines, and possibly your local Chinese and or Japanese restaurant. They lost popularity in Japan when the one Samurai Lord, got saved by a cat.
The three legendary dogs, are made to look more like Fuu-Dogs than say a Husky, Labradore, or Golden Retriever. Suicune does have the snout, but Entei in particular is VERY Fuu-Dog-esque.
I have studied abit too much into Japanese history, legend, and such.