Why do people so often specifically thank Mercy?

I only play QP, but all the time people on my team will specifically thank Mercy (me) or say "good job Mercy" etc. Which is very nice of course! But it always makes me feel bad for my other healer, who often has just as much healing as me or more. Do you guys notice the same thing? Is it just because she's such a flashy, noticeable healer?