Ah but every living thing on the planet works in nuanced ways. If only we all worked in 0's and 1's making statistics would be easy.
I take your point though, open ended questions can be harder to quantify into usable data, but on the other side of the equation such questions can reveal patterns that weren't originally being looked for, but become apparent if a number people answer similarly.
eg:
Does your dog like tennis balls? (yes/no) This is easy to quantify and get a number from.
Does your dog like tennis balls?
responses:
He only likes green ones not yellow ones.
Yes he does.
She likes some tennis ball colours but not all tennis balls.
Yes, but he is not allowed to have them, he eats them.
Rocky has a favourite green tennis ball he can't live without, it goes everywhere with him.
No she prefers her squeaky toy.
Only if their green.
From this you get both a number of dogs that like tennis balls, but also that dogs generally seem to like green tennis balls best. Possibly because Green means go.