I've never actually applied for a job at Google, but going to 7 interviews (or however many it is now) seems like a lot more work than what they're asking for. I'd rather spend 30 minutes writing code than 7 hours on interviews, and either way you're going to have to answer technical questions at some point in the process.
Also, if you can't be bothered to spend 30 minutes proving that you can code, how much do you really want to work there? The only time I've done one of these challenges was for a company that I was really excited about working for.