I read something not too long ago, I can't for the life of me remember where, (if it was your blog, speak up and take credit!) about the responses to thank you. If I remember correctly the author was admonishing the use of responses like "sure" and "no problem" when saying thank you. S/he thought that it diminished the thank you as a no big deal kind of thing. It has had me thinking and I've come to realize that I use those two responses a lot! Once I realized it I've been thinking about whether it was okay.
Here are my thoughts, when I hold a door open for someone and they say thank you (or thanks) for some other small nicety I don't think a "you're welcome" is always necessary, a "sure" is fine. Why? Because its small and sometimes in passing there just isn't time for "you're welcome." Sometimes it isn't even a full thank you, its thanks. The informal act and giving of thanks seems to reuire an informal response. In more formal settings or when someone does something on a bigger scale "you're welcome" is the proper response.
So, what do you think is "you're welcome" always necessary or is "sure" or "no problem" okay with you?