If a company wishes to "protect" their site from crawlers, there are a number of processes that can be implemented to scare off the vast majority of people wanting the data.. Of course, there are costs associated with implementing the preventive processes, and most companies wouldn't unless they think their sites have content that needs protecting. Google is one of these companies.
Google also has the resources in spades to prevent scraping, given that most people wanting to scrape google, couldn't work at google!
If you need to get a bunch of data from google for your project, I'd suggest you look elsewhere.