ReUsable Bags-Worth the Time and Effort?

Are the reusable tote bags all stores are advertising worth the ten seconds it takes to find them in the back of your car as your running into the grocery store? Is it worth it to have these bags? Of course! Being only fourteen, I haven't yet begun to explore the world, the daily activities of people, but I do know that we can all spare five dollars and a few minutes in a small effort to save our planet.  These bags are durable, lightweight, and carry much more than expected.  $168 worth of groceries was carried in our first trip with these bags alone. In only FIVE bags. These things are incredible! Not only are they much easier to carry, but they also hold more, requiring less trips from the car. Buying only five or six of these (And getting milk/soda's/toilet paper/paper towels UNbagged) can seriously reduce landfill space. Sure the old plastic bags can and are being reused, but you can't reuse all of them, and even then they're still ending up in landfills! There are numerous Pro's to using these bags, some of which I listed above, and few Con's.
The only Con I can think of is the weight of the bags. Because they carry more, they ARE heavier, but you could fit four of the plastic bags containing groceries into a reusable tote, meaning that if you make it into your house with only two of these bags, you've really carried EIGHT bags into your house, which would be about three trips from the car. These bags save time! Another Con, however, is that the bags do eventually wear out.
In addition, most leading grocery stores offer a 5-10 cent (per bag) discount for using the new bags. This means that, since most bags go for ~$1, the bags will pay themselves off in 10-20 uses!
Invest in the bags of the future! :)