He is, in general, extremely frugal. However, he also owns a chalet and Porsche that he drives when at the private chalet (although, I'd argue that for someone worth more than 20 billion dollars, that's fairly frugal.)

I seem to recall that IKEA offers their more frequent flying employees business class tickets but if they choose to take the standard (slave) class tickets they get 50% of the difference.

I don't know if this is the case any more but I am reasonably certain it was some time ago, alas I have no source.