Reply To: May one use an escalator on shabbos?

Sam, I thought his second reason (based on Chasam Sofer was relevant):

http://hebrewbooks.org/pdfpager.aspx?req=14500&st=&pgnum=158

See also: http://www.theyeshivaworld.com/wp-content/uploads/2009/09/elevator_psak.jpg, particularly Rav Vosners’s.