We just got back and for the first half of our week long trip, we just left our backpack in the stroller outside the rides. We never put our valuables in the backpack. Those are around our necks or on our body somewhere. However, halfway through our trip, our friends who came with us (newbies) had their stroller taken, along with their backpack. They did not have their valuables in the backpack either, but DF was still VERY upset. So much so that it ruined her trip until she got it back at Lost and Found. Yes, she did get it back. We came to the conclusion that someone grabbed their stroller by mistake, thinking it was theirs and when they saw the strange backpack, returned it at Lost and Found, but kept the stroller. Probably figured that since they left their stroller back there somewhere, they would just take the one they grabbed. Needless to say, for the REST of the trip, the backpacks came with us on the rides. No, there is never a problem holding onto it on the rides, especially if you are not planning on riding any wild rides. Just sit it on the floor between your legs and enjoy the ride. Since we are talking about strollers, let me pass along a little tip. Ironically, our frends brought their own stroller thinking it would be less likely to be taken by mistake outside a ride vs. one of the millions of Disney strollers. We actually had this conversation before we left. We rented our stroller at Disney and ours was not taken but theirs was. That may have been one reason DF was so upset. Anyway, before we left, I bought a yard of brightly colored fabric at Wal Mart and everyday as soon as we got our stroller, I tied it onto the handle. We never had a problem spotting our stroller as you simply could NOT miss the bright yellow fabric tied to the handle. Just a little tip.