My co-founder and I have pitched to tens of venture capital firms in the bay area. Not once have been openly told "no". It seems all the VCs give you an open ended reply that makes you feel hopeful that they just might turn around and invest in you.
Why is this the case? Is this a norm or just a coincidence in our case?
The main reason why most VCs won't say "no" -- they don't want to completely lock themselves out of investing in your startup. Even if they're not interested now, they want to be able to approach you later if your startup does end up being a success.
A better approach is to ask them if they have any concerns or feedback. You'll get more insight into their intentions and valuable feedback on what aspect of your business to improve on.
There's also a herd mentality when it comes to investors. Sometimes they just wait to see if any other firm is going to bite first. That provides them a confirmation of sorts.
My last point would offend some people, but do take a look at their portfolio. Have they invested in any of your competitors? If so, tread carefully. You'd be surprised how often some investors end up sharing your deck with their portfolio companies if there is something that would benefit them.