Yes, that is true in most cases.  Most slots in Las Vegas pay between 85-96%, depending on where you are playing and what coin denomination you play.  Nickel slots are especially bad, as you will rarely find nickel games paying over 90% in Vegas.

The key to finding high paying online slots is to stick with online casinos that have their payouts audited each month by a reliable third party, like Price Waterhouse Coopers.

If you go to http://www.ranked-online-casinos.com/payout-percentages.html?y you will find only casinos that are audited by Price Waterhouse, one of the largest auditing firms in the world.  Their actual payout percentages are posted on this site, as well as a link to the actual report.