Google also has a pile of cash. And a fiber optic network. And millions of square feet of data center space.
Exxon:
Assets: $350bn Liabilities: $75bn
Apple:
Assets: $225bn Liabilities: $53bn
Google:
Assets: $110bn Liabilities: $15bn
If you're trying to value a stock on fundamentals alone, you should take these tangible assets (as you call them), back them out of the market cap. Then look at what kind of P/E multiple you're getting. And compare that to other companies in the industry.
The big difference here is in growth rates. Google is priced for growth. And certainly you can imagine Google growing much faster over the next decade than Exxon.