One thing that I find particularly irksome, and especially at LHR is the cash only National Express hotel shuttles;
One of my pet peeves as well, since they are chuffing expensive.
I know I am going off topic and I'm I'm sure I'm preaching to the choir regarding LHR but if there's more than 2 of you in a group it is often cheaper to book a "private" taxi than use a Hopper ...and of course if you are "brave" enough to use public transport and not encumbered by too much baggage you can easily get to a lot of the LHR hotels for free using the buses that stay within the TfL free travel zone (roughly the "perimeter road", including the Bath Road along the north side, as far east as Harlington corner and then towards Hatton Cross.)
http://www.heathrow.com/file_source/...d_Heathrow.pdf