An example is when a company (and I make no pretense about being PC here, but I've only seen this with eastern or southern european companies) has promised things that Disney cannot meet or given guests incorrect information about stuff. Want a few examples? I know you do.

A southern european company once had arranged for flights and hotel rooms for a group of about 50 guests, but had not arranged for any transportation between the airport and the park. Them not having reserved a local guide thus resulted in te group first spending a few HOURS in the airport while at first strolling through it at random without knowing where to go and what to do and then trying to contact the travel agency. The agency, in turn, phoned Disney and had the audacity to complain to Disney about how difficult it was to get to the park! In all the confusion, however, they neglected to mention this was regarding a group that wa salready in place! Thus, the puzzled Disney employee gave them the standard answer about there being regular buses from the airport to the park. :roll:
SO, the whole group of 50 people mobbed the shuttle service and they all had to pay the quite large sum perperson for the bus ride. They were NOT happy, and even less so when they discovered that the travel agency had booked their guided tour of the park for the LAST day of their four-day stay there... Can you say "DOH!"...? The DLP staff rectified all of this of course, but as usual got no gratitude from the guests, who could not see the difference between Disney and the two-bit travel agent they had bought their trip from...

Another travel agency had simply told their travellers that Mickey would meet them at the airport (they denied this even though the guests all said the same thing) and that there would be characters present at every breakfast (character breakfast every day at the cheapest hotel in the resort?). Nice going. To top it off, they had given out "vouchers" for "character photographs" to families with children. Turns out, those vouchers were for some other Disney resort that the agency had arranged a trip to two years earlier.
My favourite agency, however, has to be the one whose guide apparently had to keep up a lot of false facades in front of his group of travellers. He was constantly trying to persuade the FastPass attendants to let his "VIP" group enter the attractions through the fastpass entrance without fastpasses, and according to my Finnish friend who worked at the three-star hotel where they were staying the guide kep asking for free stuff and special treatment at the hotel since the agency had told the guests that they were booked in the best hotel in the resort!
Way to go - I hope the guests didn't ask any embarassing questions when they passed under the Disneyland Hotel on their way into the park every morning... Having worked at a travel agency myself, I can totally relate to this poor guide's troubles - the whole travel business is a web of constant tries to tell your customers semi-truths and renaming rooms to suites etc...