Humans and space whales live in harmony among the stars. Why? Because we need them and they need us. The whales provide us with transport across the galaxy, access to resources and materials, and much-needed companionship and in return they only ask that we keep them healthy. For being such an ancient species living in deep space, they're not too bright and get themselves into all sorts of trouble.
Their docile and cuddly demeanors make for perfect company in the lonely expanse, so what kind of monster WOULDN'T do their best to make sure they're happy and disease-free?
Naturally, clinics have sprung up across the stars offering these magnificent beasts relief from whatever ails them in return for a number of goods and/or services. Usually cash.