When my wee boys stand on their Lego I see it as a wonderful teachable moment. Lego is a great company to provide me with so many educational opportunities.
When you as a child stand on Lego you learn that you should tidy things away when done, when as an adult you stand on it you learn that you need to have a talk with the kid about tidying things away. Or to tidy it away after you've built another spaceship.
And when an adult stands on it in front of the kid, the kid learns lots of interesting new words!
Lego: you're never not learning.
The only real problem I have with Lego is the price of some of the items. A cursory search will bring you across £500 Technic sets... which is utterly bloody ridiculous.