There are a lot of ill people in the world. Cancer, infections, HIV, accidents, and so on. Not only are the ill people affected by their illness: their friends and family are affected too.
Unsurprisingly, many of those friends and family are desperate to find hope. For many of them, religion is their outlet. "I thank God for healing little Sally;" "Praise to God for curing our grandma's cancer." And so on.
But I have a novel idea: how about you thank the doctors and nurses that are working long, hard hours to treat your loved ones?
To my way of thinking, giving your god all the thanks when there are professionals working 20-hour days to treat your loved ones is just...insensitive. I understand the need to rationalize, to find hope, to pray for help. I wouldn't begrudge anyone that.
But to take the tangible work of real people and give the credit to someone that may or may not be there is selfish. In any other line of work, you'd be mad if you did all the work and your boss gave your coworker all the credit, without acknowledging your work.
The healing of bodies should be no exception to that principle. Give credit where credit is (deservedly) due.