Everything you possibly could have wanted to know about airport taxi tariffs can be found at this link:
http://www.aresep.go.cr/docs/RRG-7976-2008%20extraordinaria%20taxi%20aeropuerto.pdf.
For whatever it is worth, the correct fare at current rates on an unaltered meter with no waits for the 19kms from the airport to the front door of the SL should be 7245 colones (405 for the 1st km and 380/km thereafter) which @ a 520c/$ exchange rate would be just under $14. Any delays should not add significantly to that amount unless you were at a dead stop for significant amounts of time (another $4.25 if you sat parked for a full hour), but dead stops of more than a minute or so have never happened to me in all my experience. Do they have added expenses that red cabs don't have? Of course, I have no idea what sort of cut Alterra (the airport managment company) gets on the higher "official" airport taxi rates, but it seems to me that still allows for a significant profit advantage of the orange airport taxis over the regular red cabs. Do they wind up driving empty back to the airport? Sure, if they don't get dispatched to someone who calls in for a ride back to the airport. But you can bet the red cabs wind up burning a lot of gas just driving around cruisng for fares too. Personally, I wouldn't start take up any special collections for these orange taxi guys any more so than I would for the red ones or even the pirates. And at $20-22 for a 20 minute trip, which can be nearly as easily done for a couple of bucks using the bus and a local city cab, I'm not so inclined to add any more to that already high fare.
I'd also like to know where El C read that it is
"customary" to tip the taxi driver a couple bucks per bag, if he helps you with your luggage IN CR. Where is he getting that? Customary to whom? That might be true in the US but that is the first I've heard of anything like that in CR. Besides, how much time does it take or how hard is it to lift a bag and put it in the trunk or back seat? $2 seems like an overly generous compensation for so little effort in a country where people typically only make $20/day.
Personally, I never travel with so much luggage that I can't easily handle it myself and I'd sooner bring my bag in the cab with me for security reasons anyway. I have no problem tipping regular cabbies with the loose change from whatever the fare comes out to (IF I feel they haven't already ripped me off in some way), EVEN THOUGH even that is not "customary" amongst ticos. On an already HIGH FLAT fare, I figure I've already paid enough for the service. IF they feel they aren't making enough, they can take up the official fares with the appropriate regulatory authorities and get the fares raised YET AGAIN and if they do I'm willing to bet that more and more guys will wind up taking the Interbus option.
BTW, brother Pierre should learn to use the search function (also why is this question in "Roll Calls!" rather than "Transportation"?). Not only has the side topic of tipping been discussed ad infinitum, but the question of airport taxi fares has also been asked and answered innumerable times. Here is just one link to a thread including my own very COMPREHENSIVE discussion of airport transportation alternatives:
http://www.costaricaticas.com/phpBB2/viewtopic.php?t=21954