Well, if you can look someone's portfolio up online then, by default, they have a portfolio. What you're not getting from that type of search is the thousands of people who don't have a portfolio online.

Here's my github url: https://github.com/wwalser

That shows very little public activity. However, even that amount would be impressive to me if I saw it from a candidate. The reason is that, when interviewing a someone from a product company, I implicitly understand that they are going to have thousands of lines of code written for a private company (and therefore not publicly available). In my case http://askinline.com is that work.

Hope that perspective is helpful.