Not taking on ANY credit is not smart and can actually hurt your credit score more than a few late payments. Cell phone and utility bills don't positively affect your credit score at all, but they can negatively affect it if you are late on payments. Only loans and revolving credit help you out.
I have a house that has a fixed-rate 30 year loan and a tenant living in it paying off the entire principal + interest. That house is LITERALLY making me money just sitting there appreciating and I'll have it paid off far before the 30 years is up. If you can do it responsibly, going into debt now can make you a lot more money than saving up for everything. Judging from your other posts, you flatly believe that home loans are ripoffs, but I can mathematically prove that my decision to go into debt to buy the house works out better for me financially, plus I have extra money to live a better life right now.
There are a lot of reasons why going into debt is not a bad thing. You just have to weigh the interest rate against the investment potential.
To each his own, I'm not going to knock you for not going into debt, but don't act like it's the "smart" thing to do.