Yeah. Quite a few things don't work for me, for example the badges site, and i am not going to use something that doesn't work with the browser of my choice. 
Devs don't have to cover my case, but i don't  have to use their stuff either...  

 They get paid whether you use their stuff or not. Their customer is the grant foundation, not the end user. 

 Wish the grant givers would at least test, but whatever. 

 Well some end users are happy using their stuff. Just not us.  

 Doubt. Buggy apps have few users.