You're not running a charity. You're probably violating their TOS and abusing the good will they're putting out towards open source projects.

I can't believe it but your little project has for the first time in my life put me in the position of defending Microsoft. I hope they shut it down ASAP.

For Microsoft, free isn’t free… It puts them in a position of advantage. However, I still agree this is abusing goodwill and is rather disgraceful.