And ‘adopted’ can mean many things. Purchased often refers to the payment and transfer of ownership when buying an animal.You'll have to tell us why it bothers you.
My own feeling?
As far as 'honesty', all life has value.
Because someone chooses to apply the term to an animal, I can't see how their love, or where they give value, means they are cheapening or demeaning it regarding children.
According to Mirriam-Webster, 'adopting' means to take by choice into a relationship, also to sponsor the care and maintenance of. There is no denying taking on the care of animals should and must imply care, assuring welfare and health.
Feeling threatened or upset by other people's feelings or way of thinking can be exhausting and often fruitless.
Rescuing can mean you literally grabbed a hen in the middle of traffic.
Adopting can mean you got it for a shelter or another owner or anything.