[thenomad]

Since you're getting a lot of hating here, I'll just say:

1) If someone does this in my favourite coffee shop, they're polite, and they take my first "no" for an answer, I'm completely OK with this.

2) Having done similar things in the past, it's my experience that - with the caveats above - most people are OK with this.

Obviously, some level of social skill, ability to tell if your presence will be seriously unwelcome, and general politeness and diffidence is rather necessary. Don't send the guy who never washes and keeps getting complaints from women at parties. But if you pass that hurdle, you'll be fine - and as someone said below, it's not like there are enough startups out there that this is ever going to become a major problem.