Get a container such as a Cool Whip bowl with lid and fill it half full of kitty litter. Use that to store your used rubber bands. The kittly litter will absorb the fuel from the rubber bands. I have used the same rubber bands for several flights just fine. All you have to do is to stretch the rubber band before putting it on the plane. If it breaks, then it is time to replace it.
Once I purchased a new box of rubber bands from the LHS and stretched them before I put them on the plane. A lot of them broke before the first time I got them on. This was a rather busy hobby shop and somehow they had gotten pushed back on the shelf and became old and brittle...just like I am becoming. I took them back and they were skeptical about being brittle till we got another box off of the shelf and the rubber bands broke out of that box as well. Forunatly for me, I moved up into airplanes that the wing bolted on instead of rubber bands. Bigggg improvement. Good luck.