Wow, I just got back a huge project in C# from outsourced developers and while going through my code review my analysis tool revealed bunches of what it considered bad stuff
I sometimes use a WebControl that is not compulsory for a page to display. If it fails, I don't want to prevent the page from displaying. An example of a non-critical WebControl would be one that displays an advertisement.
However, I do log the error. I just don't rethrow it.