Mis-selling product

I recently rented a car via Rent a Green Car (which has since disappeared from the web but seems to be the same company as Carhire3000 and Travel Jigsaw) and very quickly regretted it. I ultimately realized that it was nothing more than a truly genius concept to rope in and get money from knee-jerk environmentalists or people who want to quickly and easily feel better about the already not eco-friendly decisions they are making (like I was at the time). Rent a Green Car operates as a kind of travel agent, regrouping worldwide car rental places and their cars – their trick is organizing the cars in terms of their CO2 emissions.
Does it work? Yes. Are they trustworthy? Seemingly so. However
1) The rate I paid was more than the walk-in rate when I arrived to the rental place. Often, dealing directly with the car rental company will find much better rates – I paid 50% more than I would have.
2) The package that you are forced to take (at least in my case) came with a full tank of gas that I had to pay for, no matter whether it was used or not. This can be very inconvenient if you are only renting for a few days or not planning to travel far. It also encourages people to use as much gas as possible in order not to waste their money – not a very green feeling.
3) This service is supposed to be open only and exclusively to UK residents. Of course, Rent a Green Car will take money from anyone, so it’s no problem to book a car, but the actual car rental agency will not be very happy with you if they see that you are not a UK resident.
What would be a better option for car renters to be more eco-friendly?
1) Consider other possible modes of transport. Or car-sharing companies.
2) Do your own research and choose smarter cars – this is not difficult with Google, to simply research the emissions of various models.
Though it looks like a great idea, it turns out that the site is just another money-making outfit, targetting people soft on the green idea, like any of the other thousands of polluting products marketed as supposedly eco-friendly.