Events: Toddler, Diaper Covers

Cloth Diapering-- Are Liners Necessary?

Are diaper liners necessary when using prefolds w/ diaper covers? AND-- when venturing out on the town, what do you do with the dirty cloth diapers-- rinse them in the public restroom and then carry them with you in a separate bag? Do they smell? Thanks ladies... any input would be greatly appreciated!