Oh that's so nice that they gave you a voucher! I know they lost the luggage, but with the re-routing, it does happen. On our first family trip to Orlando, in 2010, our flight back home was delayed by 7 hours. We were supposed to leave at 5pm, and international flights, checkin was 3 hours early. So we had to be there at 2 and we had to sit in the line for HOURS before they finally told us we were delayed until Midnight. They gave us each a $15 dinner voucher for the airport, and that was the extent of the compensation we got. Because we were delayed so long, we missed our connection in Amsterdam...we had flown out of Dusseldorf, Germany because it's about equal distance as Amsterdam, and it was cheaper. When we landed in Amsterdam, we were told that they didn't have any other flights going to Dusseldorf to put us on, and there were about 30 people on our flight who were going there and had missed their connections. So they chartered a bus for us instead of setting up a new flight or trying to get us on existing flights.
We were to pick up our luggage from carousel 20 and then we'd get on the bus....no time to eat anything, we couldn't stop....just get your luggage and go. Then the luggage never came..they told us they had changed the carousel....so we were led to a different one and everything came out except one of our carseats. (It's illegal not to have your child in a carseat in Germany, so without it, we couldn't get home) We spent an hour and a half waiting for the carseat...everyone was on the bus waiting for us. They had told us we couldn't stop for food, we'd be given sandwiches on the bus. We were finally told we couldn't wait any longer, we needed to board the bus, they lost the carseat. We get on the bus, starving and exhausted...they had distributed the food while we were waiting for the carseat and had given our share out among the people on the bus, so there was nothing left for us. They had broken the clasp on one of the suitcases, and we were facing the prospect of not being able to get home because of the missing carseat. We were very fortunate that we went within about 15 minutes of my in-laws' house in getting to Dusseldorf, so we asked the driver to let the kids off the bus at a gas station where my in-laws could pick them up, as they had carseats, and that way at least the KIDS could be fed as it was now 7pm Dutch time and we hadn't eaten in about 16 hours, and it was another 3 hours to Dusseldorf by bus.
We ended up putting in a claim for compensation because I guess the law says that if your flight is delayed more than 5 hours when the flight is more than 1500 miles, they are required to give you a portion of the costs back, and of course we wanted compensation for the suitcase that was broken, not to mention that we paid for a FLIGHT to Dusseldorf, not a bus ride, but they denied our claim. We got NOTHING. Not a cent. I don't even understand how they could get away with that. They should have at least had to pay for the suitcase.
We ended up getting the carseat back. We called when we got home and they told us it was in Dusseldorf, we could come pick it up. DH told them they had a couple of options. 1, they could buy us a new carseat. 2, they could ship the carseat to us at their expense, since they lost it. 3, they could compensate him for his time lost on his job because he had to go and pick it up from them, and as an engineer, they charge 100 euros an hour for his time, and it's a 2 hour drive each way. So he'd have to take 4 hours off of work to go pick it up. Their choice. They shipped it to us. Worst customer service EVER, though...no compensation for the loss of the one flight, no food or drink, no time to stop and GET food, loss of luggage, broken luggage, and they wanted us to come pick up the thing they lost? We won't fly KLM ever again. Too bad we didn't know about twitter then, or have smartphones to use it. Nowadays, a couple of tweets would shame them into doing something about it.